We've wrapped up our live coverage for the day. You can read more on Russia's invasion of Ukraine here, or scroll through the updates below.
Russian President Vladimir Putin met with Chinese Defense Minister Li Shangfu in Moscow on Sunday, with both sides hailing their close military cooperation, according to the Kremlin.
Putin said Chinese President Xi Jinping's recent visit to Russia was "very productive," and relations between Russia and China are developing well in all areas, the Kremlin said.
️Russia said Putin used the meeting to highlight military cooperation as a key area of strength between the two countries.
In his first overseas trip since becoming defense minister, Li said Moscow and Beijing "have very strong relations, that far surpass the military-political alliances of the Cold War," according to the Kremlin statement.
Russian Defense Minister Sergei Shoigu was also present at the meeting.
Key background: The latest diplomatic sit-down between Russian and Chinese officials comes at a time of increased Western scrutiny about the two governments' relationship — and how it plays into the war in Ukraine.
Putin and Xi posed as peacebrokers during a friendly visit in Moscow last month, but the Chinese leader's proposals on ending the conflict in Ukraine include no provision that Moscow withdraw its troops from Ukrainian land, and was drawn up without any involvement from Kyiv.
While China and Russia have strengthened ties in recent months, the US has not seen evidence that China has provided systemic material support to the Kremlin, as Putin looks for avenues to evade Western sanctions and backfill its military, according to senior US Treasury officials.
CNN's Sam Fossum and Simone McCarthy contributed to this report.
The European Commission denounced a decision by Poland and Hungary to ban imports of grain and other agricultural products from Ukraine.
"Unilateral actions are not acceptable. In such challenging times, it is crucial to coordinate and align all decisions within the EU,” EU Commission spokesperson Arianna Podestà told CNN in a statement Sunday.
Podestà said trade policy is an "exclusive competence" issue, referring to the alliance's policies around decisions that must be made as a group, and not by individual member states.
The commission is requesting more information from the involved countries to assess the measures, the spokesperson said.
The bans in question: On Saturday, Poland banned imports of grain and other food products from Ukraine "to protect the Polish agricultural market against destabilization,” the Polish prime minister’s office said in a statement.
Hungarian Agriculture Minister István Nagy announced Sunday that Budapest would take similar steps, temporarily banning the import of grain, oil seeds and other agricultural products from Ukraine.
“The government is committed to representing the interests of the Hungarian economic society," Nagy said in a Facebook post Sunday, adding he was taking the step "in the absence of meaningful EU measures."
What led up to the bans: When Russia invaded Ukraine, it blocked ports and sea routes used to export Ukrainian grain to Africa and the Middle East. Fearing widespread famine, the European Union lifted duties on grain from Ukraine to ease distribution to those global markets.
Ukrainian grain has since flowed into Poland, but much of it has remained in the country, bringing down the price and causing Polish farmers to suffer significant financial losses.
That's spurred protests and calls for the European Commission — effectively the EU's cabinet government — to intervene. But the international body only spurred further anger when it announced a draft decision to extend duty-free and quota-free imports of Ukrainian grain until June 2024.
CNN's Mariya Knight and Jonny Hallam contributed to this report.
The death toll from Friday's Russian missile barrage on residential buildings in Sloviansk, Ukraine, has reached 15, according to a regional Ukrainian official.
A further 24 people were wounded in the strikes, up from the previously reported total of 22, Pavlo Kyrylenko, the head of the Donetsk region's military administration, said in a Telegram post Sunday.
Kyrylenko said rescuers pulled five people, including a 14-year-old girl, from under the rubble. The bodies of 10 of the victims were recovered.
At least eight explosions rocked the city Friday afternoon local time, as Russian forces targeted it with S-300 rockets, according to Sloviansk Mayor Vadym Liakh. The strikes hit apartment buildings, houses, administrative buildings and a schoolyard.
The embattled city of Bakhmut — currently the scene of the fiercest fighting between Russia and Ukraine's troops — has been rocked by nearly 100 shellings over the last 24 hours, a Ukrainian army spokesperson told CNN.
Some 30 firefights have taken place as both militaries wage street-by-street — and even house-by-house — battle for control of the city, said Serhii Cherevatyi, of the Eastern Grouping of the Ukrainian Armed Forces.
New video released by Ukraine's military illustrates the intensity of the fighting.
In one, Ukrainian soldiers from the 3rd Assault Brigade can be seen firing from a position inside a shattered first-floor apartment, its corner entirely blown away.
The constant sound of gunfire exchanges and explosions speaks to what Cherevatyi described yesterday as the “bloodiest of battles, unprecedented in recent decades.”
Russia reports gains: Russia’s Ministry of Defense claimed Sunday that Wagner mercenaries have captured two more blocks in the north and the south of Bakhmut, according to RIA Novosti. Units of Russia’s Airborne Forces, the VDV, were providing support, the Defense Ministry added.
CNN is unable to independently verify the report, but the Institute for the Study of War in Washington, DC, appeared to back up the Russian claims, based on geolocated footage.
Russia targets supply route: Moscow's troops launched an assault Saturday on the town of Khromove, which lies along Bakhmut’s main supply route from Chasiv Yar to the west, Cherevatyi said.
Logistics operations were not easy, the spokesperson told CNN, but they continued.
“We can still deliver ammunition, provisions, medicines, food, and take our wounded out. Of course it is difficult, but it is possible,” he said. “Our artillerymen are engaged in counter-battery operations to prevent the enemy from constantly firing on the delivery routes."
Russian forces continue to mount heavy attacks on Ukrainian towns and positions in the eastern part of the country, according to new information from a Ukrainian army spokesperson.
The area between Lyman and Kupyansk — which was recaptured by Ukrainian forces six months ago, and constitutes the northernmost stretch of the front line — is under the heaviest fire with 300-400 attacks per day, Serhii Cherevatyi, of the Eastern Grouping of the Ukrainian Armed Forces, told CNN.
Ukrainian paratroopers shot down a Russian Su-25 aircraft over the nearby town of Chervonopopivka, Cherevatyi said.
All Russian offensives in the area were unsuccessful Saturday, the Ukrainian military claimed.
Kyiv's forces also reported Russian mine-laying operations in four eastern locations.
Russian forces are trying to remove children from their families in occupied southeast Ukraine in an effort to “intimidate people,” a Ukrainian military spokesperson claimed Sunday.
The warning from the official, Oleksii Dmytrashkivskyi, on Ukrainian national TV echoed claims from local Telegram groups in Enerhodar, a city in the occupied Zaporizhzhia region.
Users have shared unverified reports about children getting deported to Russian-occupied Crimea, using Zaporizhzhia nuclear power plant buses as transport.
What we know about family separations in Ukraine: The International Criminal Court (ICC) last month issued an arrest warrant for Russian official Maria Lvova-Belova and Russian President Vladimir Putin over an alleged scheme to deport Ukrainian children to Russia, an alleged practice that CNN and others have reported on.
The Ukrainian presidential office recently estimated the total number of Ukrainian children forcibly removed from their homes is at least 20,000. Thousands of cases are already under investigation, Kyiv has said.
On Monday, authorities in Ukraine's southern Kherson region said 24 more children have returned home after being taken to Russian territory. Others have recently returned to parents in the Kharkiv and Zaporizhzhia regions.
Ukrainian special forces training on US-made Black Hawk helicopters have shown immediate promise, the Ukrainian Ministry of Defense said Sunday.
The Black Hawks are superior to helicopters Ukraine had been using, the Mi-8 and Mi-24 in “nearly all respects,” according to the ministry.
“Recently, the Ukrainian Defence Intelligence special forces have conducted regular training on the Black Hawk multi-purpose helicopter in one of the frontline areas. Special forces practiced landing combat groups on the battlefield, evacuation, landing from landing cables, and night flights,” it said in a statement.
Ukrainian pilots were impressed with the aircraft's “reliability, ease of operation and combat survivability," state media Ukrinform quoted a helicopter flight engineer as saying.
"Having experience operating the Mi-8 and Mi-24, we flew on the Black Hawk on the first day we received it. We just sat down and made the flight," Ukraine's military intelligence service quoted a Ukrainian pilot as saying.
The skill of Ukraine’s pilots over the past year has risen “tremendously” the pilot added.