This was CNBC's live blog tracking developments on the war in Ukraine. See here for the latest updates. 

Bakhmut remains the hot spot in the war between Ukraine and Russia — the head of Ukraine's armed forces described the situation in the city as "difficult," although Ukraine's President Volodymyr Zelenskyy said intense fighting there is taking a big toll on Russia's forces.

Zelenskyy said Sunday evening that since March 6, Ukraine's forces had "managed to eliminate more than 1,100 enemy soldiers."

The commander of Ukraine's ground forces Colonel-General Oleksandr Syrskyi said Monday that "Wagner's assault units are advancing from several directions, trying to break through the defenses of our troops and advance to the central districts of the city," according to the latest post on the Military Media Centre, translated by NBC News.

In other news, the Wagner Group has likely lost access to recruiting in Russian prisons because of ongoing disputes with the Russian defense ministry and could be pivoting recruitment efforts toward free Russian citizens, the U.K. said Monday.

Since the start of March 2023, Wagner has set up outreach teams based in sports centers in at least 40 locations across Russia and has given careers talks in schools, Britain's Ministry of Defence noted in an intelligence update.

U.S. defense budget soars to $886 billion, the Pentagon's largest request

The Biden administration's proposed budget request for the fiscal year 2024 sets defense spending at $886 billion.

The defense budget includes about $1.7 billion to help Ukraine rebuild its critical infrastructure amid Russia's war. The budget will also finance multi-year contracts for missiles and other munitions to replenish U.S. stockpiles.

The federal budget also includes $63.1 billion for the State Department and USAID.

Secretary of State Antony Blinken said in a separate statement that the proposed funding "will make it possible for us to continue to promote U.S. national interests, lead the world in tackling global challenges, and continue support for the people of Ukraine."

— Amanda Macias

Three ships leave Ukraine under Black Sea Grain Initiative

Three ships carrying 160,560 metric tons of grain and other agricultural products left Ukraine's Chornomorsk and Odesa ports Monday.

One ship is destined for Spain and is carrying corn. Another ship is headed to China and is also carrying corn. The third ship is destined for Turkey and carries wheat.

The Black Sea Grain Initiative, a deal brokered last July between Ukraine, Russia, Turkey and the United Nations, eased Russia's naval blockade and saw three key Ukrainian ports reopen.

So far, more than 700 ships have sailed from Ukrainian ports.

— Amanda Macias

Growing shortage of skilled workers at the Zaporizhzhia nuclear power plant, Ukraine says

Ukraine's military said that there is a shortage of skilled workers at the Zaporizhzhia nuclear power plant due to Russia's ongoing war.

"The shortage of skilled workers who can ensure the vital activity of the nuclear power plant is growing catastrophically," Ukraine's military said in an update posted on Facebook and translated by NBC News.

The nuclear power plant, Europe's largest, was captured by Russian forces in the early days of the full-scale invasion of Ukraine.

Ukraine's military also said that "the Russian occupiers employed people without the appropriate education and experience at the nuclear power plant."

"All this can lead to unpredictable consequences," the group added.

— Amanda Macias

UN says at least 8,200 killed in Ukraine since start of war

The United Nations has confirmed 8,231 civilian deaths and 13,734 injuries in Ukraine since Russia invaded its ex-Soviet neighbor a year ago.

The Office of the U.N. High Commissioner for Human Rights said the death toll in Ukraine is likely higher, because the armed conflict can delay fatality reports.

The international organization said most of the civilian casualties recorded were caused by the use of explosive weapons with a wide impact area, including shelling from heavy artillery and multiple launch rocket systems, as well as missiles and airstrikes.

— Amanda Macias

Moscow may extend Black Sea Grain deal but 'only for 60 days,' Russian official says

Russian Deputy Foreign Minister Sergey Vershinin said at a briefing in Geneva that Moscow may extend its participation in the Black Sea Grain deal but only for 60 days, according to Russian-state media RIA Novosti.

The Black Sea Grain Initiative, a deal brokered in July among Ukraine, Russia, Turkey and the United Nations, eased Russia's naval blockade and saw three key Ukrainian ports reopen. The deal is set to expire on March 18.

"Our further position will be determined depending on the real – not in words, but in deeds – progress towards the normalization of our agricultural exports, including bank payments, transport logistics, insurance, unfreezing of financial activities and the supply of ammonia through the Togliatti-Odessa pipeline," Vershinin said, according to an NBC News translation.

So far, more than 700 ships have sailed from Ukrainian ports.

— Amanda Macias

Talks underway to extend Black Sea grain deal

Negotiations began on Monday between U.N. officials and Russian Deputy Foreign Minister Sergei Vershinin on a possible extension to a deal allowing the safe export of grain from Ukraine's Black Sea ports, the Russian diplomatic mission in Geneva said.

The Black Sea grain initiative, brokered between Russia and Ukraine by the United Nations and Turkey last July, aimed to prevent a global food crisis by allowing Ukrainian grain blockaded by Russia's invasion to be safely exported from three Ukrainian ports.

The deal, which was extended for 120 days in November, is up for renewal on March 18.

Russian officials say that although the country's agricultural exports have not been explicitly targeted by the West, sanctions on its payments, logistics and insurance industries have created a barrier for it being able to export its own grains and fertilizers.

— Reuters

Ukraine's first lady calls for more Western weapons

Ukrainian first lady Olena Zelenska called for more Western weapons as her country continues to fight off a colossal Russian invasion.

"Somebody perhaps thinks that it is out of place for a president's wife to ask for weapons, but I will ask for it, because it's our salvation," Zelenska told MSNBC's "Morning Joe" in an exclusive interview.

Zelenska added that even the children of her country know how crucial Western arms have been on the battlefield.

"Children know what HIMARs is, children know what the tank is," she said, adding that kids shouldn't know that much about military weaponry. "But this illustrates just how much we need this help. Because every child in Ukraine knows that we need more and we need faster."

Watch the full interview here.

— Amanda Macias

Spain trains Ukrainian military on Leopard 2A4 Tanks

The Spanish military shows Ukrainian soldiers how to use Leopard 2A4 tanks during a training exercise conducted at the San Gregorio military base outside Zaragoza, Spain.

The military aid for Ukraine has stoked tensions within Prime Minister Pedro Sanchez's governing coalition with its junior partner, the far-left Unidas Podemos party, urging the administration to focus on pushing for peace instead of sending weaponry. 

- Getty Images

Georgian PM tells Ukraine's Zelenskyy not to meddle in his country

Georgian Prime Minister Irakli Garibashvili accused Ukraine's President Volodymyr Zelenskiy of meddling in his country's political situation by commenting on protests there last week, prompting an angry response from Kyiv.

During the protests against a "foreign agents" law that critics said signalled an authoritarian shift in Georgia, Zelenskiy thanked protesters for waving Ukrainian flags, saying it showed respect, and he wished Georgians "democratic success".

Last Friday, Georgia's parliament dropped the bill, which had threatened to harm Tbilisi's bid for closer ties with Europe. Critics had said it was inspired by a 2012 Russian law that has been used widely to crack down on dissent in Russia.

"When a person who is at war... responds to the destructive action of several thousand people here in Georgia, this is direct evidence that this person is involved, motivated to make something happen here too, to change," Garibashvili said in an interview with the Georgian IMEDI television broadcast on Sunday, referring to Zelenskiy.

"I want to wish everyone a timely end to this war, and peace," Garibashvili added.

However, Ukraine's foreign ministry spokesperson Oleh Nikolenko accused Garibashvili of repeating "Russian propaganda" by suggesting that Kyiv sought to draw Georgia into its conflict with Moscow.

"We categorically reject such claims, which have nothing to do with reality. The Georgian authorities are looking for an enemy in the wrong place," Nikolenko said on Facebook on Monday.

"Ukraine has been and will remain a friend of the Georgian people, whom we do not wish to stop (in their task of) building a European future."

Despite Garibashvili's comments, Georgian public opinion is strongly pro-Ukrainian and anti-Russian. Georgia fought its own brief war with Russia in 2008 over the status of two Moscow-backed breakaway regions, Azkhazia and South Ossetia.

Georgia and Ukraine both aspire to join the European Union one day.

— Reuters

A day in the life of a Ukrainian artillery unit in Donetsk

Ukrainian servicemen from the 10th Brigade aim a D-30 Howitzer towards Russian infantry along the frontline outside of Soledar, Ukraine on March 11, 2023. The artillery battle between Ukranian and Russian forces near Soledar has been intense for months. 

The cannon is inherited from the Soviet era but the 122mm ammunition comes from Western countries.

-Getty Images

China's President Xi plans to speak with Ukraine's Zelenskyy, WSJ reports

Chinese President Xi Jinping plans to speak with his Ukrainian counterpart President Volodymyr Zelenskyy for the first time since Russia invaded Ukraine a year ago, according to the Wall Street Journal.

Citing people familiar with the matter, the newspaper said the call would probably take place after President Xi visited Moscow, an event that could take place next week, Reuters and the WSJ reported today.

The WSJ said that President Xi's likely virtual meeting with President Zelenskyy comes as China looks to play more of an active role in brokering an end to the war.

— Holly Ellyatt

Kremlin tight-lipped on Xi Russia visit rumors

The Kremlin's press secretary said Monday that it won't comment on a report by Reuters that suggested Chinese President Xi Jinping could visit Russia to meet President Vladimir Putin as soon as next week.

Asked about the report, which cited unamed sources, Kremlin spokesman Dmitry Peskov said that there was "nothing to say on this topic," news agency Ria Novosti reported.

"As a rule, the announcement of official foreign visits is carried out simultaneously by mutual agreement of the parties," Peskov said, adding that an announcement would be made when both parties are ready.

There have been several reports suggesting that a visit by President Xi Jinping to Russia could take place in March or April although both sides have been tight-lipped about the plans. The Wall Street Journal reported in February that the Chinese leader is expected to use Moscow trip to push for multiparty peace talks to find an end to the war in Ukraine.

— Holly Ellyatt

Executed soldier was a Moldovan citizen, ministry says

A Ukrainian serviceman who appeared to be executed by Russian troops in graphic footage that emerged last week was a citizen of Moldova, according to the Ministry of Foreign Affairs and European Integration of Moldova.

Oleksandr Matsievsky was named last week as the Ukrainian soldier seen to be executed while standing unarmed in a trench. The footage, which emerged last week, showed Matsievsky as a prisoner of war, smoking a cigarette before saying "Glory to Ukraine!" to the camera before he's shot by automatic weapons. Ukraine launched an investigation into the killing, calling it a war crime.

In a Facebook post Monday, Moldova's foreign ministry said that the soldier was one of its citizens.

"After the Ukrainian side confirmed the fact that the Ukrainian serviceman executed by Russian soldiers is Oleksandr Matsievsky, the Ministry of Foreign Affairs strongly condemns the killing of a citizen of Moldova."

"This is an act that can be qualified as a war crime and gross violation of international humanitarian law. We express our deepest condolences to the family and friends of Oleksandr Matsievsky," the ministry said.

Ukraine's president conferred a posthumous "Hero of Ukraine" award on Matsievsky over the weekend. On Sunday evening, President Volodymyr Zelenskyy said he was "a man whom all Ukrainians will know. A man who will be remembered forever. For his bravery, for his confidence in Ukraine and for his 'Glory to Ukraine!'"

— Holly Ellyatt

China's Xi plans Russia visit as soon as next week, sources say

Chinese President Xi Jinping is planning to travel to Russia's capital, Moscow, to meet his counterpart, Vladimir Putin, as soon as next week, people familiar with the matter said.

China's foreign ministry did not immediately respond to a request for comment and the Kremlin declined to comment.

No other details were immediately available. The sources briefed on the matter declined to be identified given the sensitivity of the issue.

— Reuters

Ukraine claims more than 1,000 Russians killed in Bakhmut in last week

Ukraine's President Volodymyr Zelenskyy said ongoing fighting in the besieged city of Bakhmut in eastern Ukraine is taking a big toll on Russia's forces.

In his nightly address Sunday, Zelenskyy said that "in less than one week — since March 6 — in the Bakhmut sector alone, they managed to eliminate more than 1,100 enemy soldiers."

He added that Russia had also seen 1,500 soldiers suffer wounds that would prevent them from fighting. In addition, dozens of units of Russian equipment were destroyed, Zelenskyy said, and more than 10 Russian ammunition depots were burned. CNBC was not able to verify the claims.

There have been questions over how long Ukraine could choose to defend Bakhmut, a city almost completely surrounded by Russian forces, with mercenary fighters from the Wagner Group advancing into parts of the city. Last week, Ukraine said it would continue to defend Bakhmut, however, and would send in reinforcements.

The commander of Ukraine's ground forces Colonel-General Oleksandr Syrskyi said Monday that that "the situation around Bakhmut remains difficult," noting that "Wagner's assault units are advancing from several directions, trying to break through the defenses of our troops and advance to the central districts of the city," according to the latest post on the Military Media Centre, translated by NBC News.

"In the course of fierce battles, our defenders inflict significant losses on the enemy. All enemy attempts to capture the city are repelled by artillery, tanks, and other firepower," Syrskyi said, adding that "the defense of the fortress continues."

— Holly Ellyatt

Wagner Group chief likely pivoting recruitment toward Russian citizens

Yevgeny Prigozhin, the owner of Russia's mercenary force known as the Wagner Group, has likely lost access to recruiting in Russian prisons because of his ongoing disputes with top Russian defense officials, and is "highly likely pivoting recruitment efforts towards free Russian citizens," the U.K. said Monday.

Since the start of March 2023, Wagner has set up outreach teams based in sports centers in at least 40 locations across Russia, Britain's Ministry of Defense noted in an intelligence update on Twitter.

"In recent days, masked Wagner recruiters also gave career talks in Moscow high schools, distributing questionnaires entitled 'application of a young warrior' to collect the contact details of interested pupils."

The Wagner Group has been fighting in eastern Ukraine for months, alongside regular Russian units, but Prigozhin has had a high-profile spat with Russia's Ministry of Defense after criticizing the military strategy in Ukraine.

The Wagner Group had been allowed to recruit prisoners to fight in its forces in Ukraine and the U.K. said it believed that around half of the prisoners Wagner has already deployed in Ukraine have likely become casualties. "The new initiatives are unlikely to make up for the loss of the convict recruit pipeline," the British defense ministry said.

"If the ban endures, Prigozhin will likely be forced to reduce the scale or intensity of Wagner operations in Ukraine."