Ukrainian President Volodymyr Zelensky arrived in Prague on Thursday in a diplomatic flurry in NATO countries as Kyiv pushes to join the defence alliance and demands more weapons for its counteroffensive against Russia.
Wagner chief Yevgeny Prigozhin is still in Russia, Belarus's president said earlier, raising questions about the deal to end the mercenary leader's mutiny last month.
Zelensky made an official visit to Sofia on Thursday to discuss NATO membership and weapons deliveries with Bulgaria, a major supporter and ammunition producer.
He then headed to Prague to meet Czech counterpart Petr Pavel before scheduled talks in Istanbul on Friday with Turkish leader Recep Tayyip Erdogan, an important broker in the conflict.
Zelensky told reporters that slow weapons deliveries to Ukraine delayed Kyiv's planned counteroffensive, allowing Russia to bolster its defences in occupied areas.
In his one-day Sofia visit, Zelensky held talks with Bulgarian Prime Minister Nikolay Denkov and met high-level officials including President Rumen Radev.
Bulgaria and Ukraine also signed a joint declaration on the Euro-Atlantic integration of the war-torn country and a memorandum of cooperation in the field of energy.
The Kremlin criticised Zelensky's visit to Bulgaria, saying the Ukrainian leader was trying to "drag" other countries into the conflict.
The Kremlin said Ukraine's goal of joining the world's most powerful defence alliance threatened its security before launching its invasion in February 2022.
- Prigozhin 'not in Belarus' -
Belarus leader Alexander Lukashenko mediated a deal to end Prigozhin's revolt -- the most serious challenge to Russian President Vladimir Putin's rule -- that was to see the mercenary head into Belarusian exile.
"As far as Prigozhin is concerned, he is in Saint Petersburg... He is not in Belarus," Lukashenko, who has ruled isolated Belarus for nearly three decades, told reporters from foreign media outlets in Minsk.
Lukashenko said he knew "for sure" that Prigozhin was free.
The Kremlin said it was "not following" Prigozhin's movements, nearly two weeks after the mutiny that saw armed fighters march toward Moscow.
Lukashenko said Wagner mercenaries have not established a base in Belarus yet, despite a Kremlin offer for attempted mutiny participants to relocate.
Images broadcast by Russian media on Wednesday showed police entering Prigozhin's residence, a vast and luxurious mansion with a helicopter parked in the grounds, reportedly on June 25.
The failed insurrection has called into question the future of Wagner, which has been accused by the West of destabilising volatile countries in the Middle East and Africa.
- 'Ceiling started to fall' -
Lukashenko's comments came hours after what the mayor of Lviv said was the biggest attack on civilian infrastructure in the western Ukrainian city since the start of the Russian offensive.
Interior Minister Igor Klymenko wrote on Telegram that the missiles had struck a residential building and destroyed its upper floors.
At least five people were killed in the attack and another 37 were wounded, including a child, officials and the emergency services.
UNESCO condemned the bombing of a historic building in Lviv and expressed "its sincere condolences" to the victims' families, saying the attack violated international conventions protecting heritage and cultural property during armed conflict.
Russia's defence ministry said its long-range, precision strikes overnight had hit all the designated targets, in a statement that did not specifically mention Lviv.
Rescuers were working to reach those still trapped, and AFP footage showed emergency responders clearing rubble and wood from the gutted first floor of a building.
Cars covered in dust and with their windows blown out lined a pavement piled with debris.
"I woke up from the first explosion, but we didn't have time to leave the apartment," Olya, 37, told AFP.
"There was a second explosion, the ceiling started to fall, my mother was immediately hit," she said.
"I got to the window, started screaming, and in about half an hour the rescuers got to me, took me out and took me to the 8th hospital," Olya added.
"I came back and found out that my mother had died, my neighbours had died. At this point, it seems that I was the only one who survived from the fourth floor. It's a miracle."
"There will definitely be a response to the enemy. A tangible one," Zelensky said.
While Russia regularly pounds Ukraine with missiles, artillery and drones, the Lviv region, hundreds of kilometres from the front lines and near the Polish border, has largely been spared.
Ukraine has recently bolstered its air defence systems with Western-supplied weapons and the number of Russian missiles and drones breaking through has diminished.
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