Ukraine said on Monday that Russian forces were "very far" from capturing the eastern town of Bakhmut and that fighting raged around the city administration building where the Wagner mercenary group claimed to have raised the Russian flag.
"Bakhmut is Ukrainian and they have not captured anything and are very far from doing that to put it mildly," Serhiy Cherevatyy, spokesperson for the eastern military command, said.
Earlier, Russia's Wagner mercenary group claimed it had captured the town hall in the Ukrainian eastern town of Bakhmut, giving it "legal" control, but Ukraine said its forces still held the town.
Wagner head Yevgeny Prigozhin posted a video on his Telegram channel showing him holding a Russian flag, which he said his forces would plant on Bakhmut's town hall.
"This is the Wagner private military company, these are the guys who took Bakhmut. In a legal sense, it's ours," Prigozhin said.
President Volodymyr Zelenskyy on Sunday praised Ukrainian troops' defense of the city, much of which now lies in ruins.
"I am grateful to our warriors who are fighting near Avdiivka, Maryinka, near Bakhmut... Especially Bakhmut! It's especially hot there today!" Zelenskyy said.
The Russian army, supported by the Wagner group, has pressed hard to surround Bakhmut hoping to claim a battlefield victory after the string of humiliating reversals.
Here are some of the other notable developments concerning Russia's war in Ukraine on Monday, April 3:
Rheinmetall to open maintenance hub for Ukraine weapons
German arms firm Rheinmetall says it will soon open a maintenance center in Romania for military equipment used in Ukraine's battle against invading Russian forces.
The company said the "service hub" near Satu Mare in northern Romania, close to the border with Ukraine and Hungary, was set to become operational before the end of April.
The maintenance center will "play a central role in maintaining the operational readiness of Western combat systems in use in Ukraine and in ensuring their logistical support," Rheinmetall said in a statement.
Leopard 2 battle tanks, which Germany recently shipped to Ukraine, as well as self-propelled howitzers, Marder infantry fighting vehicles, Fuchs armored transport vehicles, and military trucks could all be serviced at the new hub.
The hub could also service NATO combat vehicles, Rheinmetall added, saying this would give NATO's eastern flank "shorter reaction times."
First Polish MiG-29 fighters are already in Ukraine
The first Polish MiG-29 fighter jets have arrived in Ukraine, the Polish president's foreign affairs advisor Marcin Przydacz says.
"According to my information, the process has already been completed, that is, the handover of the first part," he said.
In mid-March, Polish President Andrzej Duda announced the delivery of four fully operational MiG fighter jets to Ukraine. More MiG-29s would be serviced and prepared for a later transfer, he added.
Slovakia is also gradually delivering 13 MiG-29s to Ukraine, some are not functional and will be cannibalized for spare parts. The MiG-29 is a twin-engine fighter jet of Soviet design, which is considered to be extremely maneuverable.
Putin creates fund for soldiers fighting in Ukraine
Russian President Vladimir Putin signed a decree creating a special fund "Defenders of the Fatherland" to support soldiers fighting in Ukraine and their families.
The measures are "aimed at ensuring a decent life" for soldiers involved in the Ukraine offensive, and for their partners and children, according to the decree.
Putin had announced the support measure at the Federal Assembly on February 21, almost a year after he sent his troops to Ukraine.
"Our duty is to support the families that have lost their loved ones and to help them raise their children and give them an education and a job," Putin then said.
Russian investigators say suspect in war blogger killing detained
Russia's Investigative Committee says that Darya T., a suspect in the killing of war blogger Vladlen Tatarsky, had been detained.
Vladlen Tatarsky, whose real name was Maxim Fomin, was killed in a bomb blast at a cafe in St Petersburg on Sunday.
Earlier, a woman called Darya T. was identified by some Russian media as a suspect online, and Russia's interior ministry put her on its wanted list.
Russia's National Anti-terrorism Committee also said that Ukrainian intelligence had been aided in Tatarsky by "agents" from the Anti-Corruption Fund, a banned campaign group set up by jailed Kremlin critic Alexei Navalny.
Meanwhile, Kremlin spokesman Dmitry Peskov said that the assassination of Tatarsky in St Petersburg was a "terrorist act" and cited Russia's Anti-Terrorism Committee in saying that there was evidence linking Ukraine to the bombing.
Tatarsky, who had 560,000 followers on the messaging app Telegram, was one of the most prominent of Russia's war bloggers.
Habeck arrives in Kyiv on surprise visit
German Vice Chancellor Robert Habeck arrived in Kyiv for political talks on a surprise visit.
Habeck said the aim of the talks was to "give Ukraine hope" that the country will be rebuilt after the war. The talks will reportedly focus on cooperation to redevelop Ukraine's energy infrastructure.
Habeck, who is also Germany's economy minister, said investment decisions had either already been made, or were due to be made.
He was accompanied by a small business delegation including Siegfried Russwurm, president of the Federation of German Industries.
It is Habeck's first visit to Ukraine since Russia launched its invasion on February 24, 2022.
Zelenskyy to visit Warsaw on Wednesday
Ukrainian President Volodymyr Zelensky is to make an official visit to Warsaw on Wednesday, said Poland, announcing a trip.
"This is an official visit, but there will also be an element of a public nature," the head of the international policy office, Marcin Przydacz, told Polish radio station RMF FM, noting that Zelenskyy will also meet with Ukrainians living in Poland.
It would be Zelenskyy's third trip abroad since the beginning of the full-scale Russian invasion of Ukraine. In December, he visited Washington. In early February, the Ukrainian president held talks in London and Paris before traveling on to a special EU summit in Brussels.
Council of Europe and UNSECO chiefs visit Ukraine
Council of Europe Secretary General Marija Pejcinovic Buric met in Kyiv with First Deputy Foreign Minister of Ukraine Emine Dzheppar.
Dzheppar said that she thanked for Council of Europe's initiative to establish the Registry of Damages caused by Russian aggression. "We discussed further steps needed to restore justice and hold Russian war criminals accountable," she wrote on Twitter.
UNESCO Director-General Audrey Azoulay is also visiting Ukraine. Dzheppar called her visit "a huge sign of support for our efforts to protect and restore spheres of culture, education, science, youth, sport and media in Ukraine."