As the war enters its 840th day, these are the main developments.

Fighting

• The Ukrainian military said its forces were fighting fierce battles near Chasiv Yar, a strategic hilltop settlement in Donetsk, and the situation was “tense”. A civilian was killed further south on the front line near Pokrovsk, while another man was killed by Russian fire in the southern Kherson region.
• Russian journalist Valery Kozhin, who worked for Russia’s state-run NTV television channel, was killed in Ukrainian shelling of a Russian-occupied village in eastern Ukraine’s Donetsk region, Russian news agencies reported, quoting the mayor of the town of Horlivka near where the incident took place. NTV reported earlier that three of its staff, including Kozhin, had been injured and taken to hospital.
• US Defense Secretary Lloyd Austin said Russia’s advance in Ukraine’s northeastern Kharkiv region was slowing and the front line was stabilising after some allies lifted restrictions on Kyiv’s use of donated weapons inside Russian territory.

Politics and diplomacy

• Group of Seven (G7) nations meeting in Italy agreed to provide financial support of $50bn to Ukraine by the end of the year, Italian Prime Minister Giorgia Meloni said. The deal will be funded from profits on frozen Russian assets.
• United States’ President Joe Biden and Ukraine President Volodymyr Zelenskyy signed a 10-year bilateral security agreement aimed at bolstering Ukraine’s defence against Russia’s invasion and moving Ukraine closer to NATO membership.
• Ukraine also signed a 10-year security agreement with Japan. “In 2024, Japan will provide Ukraine with $4.5 billion and will continue to support us throughout the agreement’s entire 10-year term,” Zelenskyy said on X. The deal, he added, envisages security and defence assistance, humanitarian aid, technical and financial cooperation.
• The United Nations’ refugee agency UNHCR said in an annual report that about 750,000 people became newly displaced inside Ukraine last year as a result of Russia’s full-scale invasion, with a total of 3.7 million internally displaced people registered by the end of 2023. The number of Ukrainian refugees and asylum seekers increased by more than 275,000 to six million, it said.
• Human rights organisation Global Rights Compliance said in a report that Russian forces deliberately used starvation of civilians as a military tactic during the 85-day siege of the Ukrainian city of Mariupol in 2022. The report found Russian forces “systematically attacked objects indispensable to the survival of the civilian population” such as food, water, energy and access to healthcare, and also cut off evacuation routes and blocked humanitarian aid from coming in.
• Russian prosecutors said they would send Evan Gershkovich, the Wall Street Journal reporter detained in March 2023, for trial, accusing the 32-year-old of collecting information for the US CIA about a Russian tank factory. Gershkovich, who is being held in custody, has denied wrongdoing. His employer said the charge was “false and baseless” and built on lies. Biden called his detention “totally illegal”. Prosecutors did not say when the trial would start.

• The judge in the trial of director Zhenya Berkovich and playwright Svetlana Petriychuk, two leading figures in Russian theatre, agreed to a prosecution request to close the trial to the public and the media over unspecified “threats” to witnesses. The two were arrested in May last year and accused of “justifying terrorism” over their production of an award-winning play about Russian women who married Islamic State fighters. The women have pleaded not guilty and say the play was about preventing terrorism.

• German Moyzhes, a 39-year-old lawyer with dual Russian-German citizenship, was detained in Saint Petersburg with some Russian independent media reporting that he was suspected of treason. The German Federal Foreign Office told the Reuters news agency that its embassy in Moscow was in contact with Moyzhes’s family. There was no official word from Russia on the detention.

• Russia’s Admiral Gorshkov frigate and the nuclear-powered submarine Kazan, accompanied by a tug boat and a fuel ship, arrived in Cuba for a five-day visit seen as a show of force by Moscow amid rising tension over its invasion of Ukraine.

Weaponry

• Zelenskyy told a news conference in Italy that Chinese President Xi Jinping had given him his assurance in a phone call that China would not sell weapons to Russia. Speaking in English, Zelenskyy said Xi had told him that “he will not sell any weapon to Russia”. Zelenskyy did not say when the conversation took place. The last publicly known phone call between Zelenskyy and Xi was in April 2023.
• The Dutch Ministry of Defence said Kyiv’s allies will send Ukraine about 350 million euros ($376.74m) worth of 152mm shells.
• Canadian Defence Minister Bill Blair said the country would start sending a total of about 2,000 surplus unarmed rockets to Ukraine as well as a selection of other weapons.