Russian President Vladimir Putin heads to Belarus on Monday, fuelling Ukrainian fears he intends to pressure his ally to join a new offensive, as Russian drones attacked Kyiv in the latest assault targeting key infrastructure, Ukrainian officials said.

Officials in Kyiv have warned for months that neighbouring Belarus could join Russian forces and serve as a launching pad for a renewed ground attack on the Ukrainian capital.

“Protecting our border, both with Russia and Belarus – is our constant priority,” Ukrainian President Volodymyr Zelenskiy said after a meeting on Sunday of Ukraine’s top military command. “We are preparing for all possible defence scenarios.”

Putin heads to Belarus on Monday for his first visit in 3-1/2 years with the Kremlin describing it as a broad “working visit” with Belarussian President Alexander Lukashenko.

Belarus – one of Russia’s closest allies – allowed its territory to be used as a launchpad for Moscow’s Feb. 24 invasion of Ukraine, but has not joined the fighting directly. Lukashenko has said repeatedly he has no intention of sending his country’s troops into Ukraine.

Russian troops that were moved to Belarus in October will conduct battalion tactical exercises, the Russian Interfax news agency reported, citing the Russian defence ministry.

It was not immediately clear when and where in Belarus the latest in a flurry of recent exercises will be conducted.

On Monday, Russian air raids hit “critical infrastructure” in and around Kyiv, Ukrainian authorities said. Air defence systems destroyed about 15 of 20 drones directed at the capital, they said. Private homes were also damaged in the wider Kyiv region, its governor said.

“Air defence systems are at work in the region,” Oleksiy Kuleba said on Telegram. “Stay in shelters and safe places until the alarm is over. Take care of yourself and loved ones.”

Several loud blasts were heard, but it was not immediately clear whether they were air defence systems destroying the drones or drones hitting their targets.

Emergency power cuts were re-introduced in Kyiv after the attacks, electricity provider YASNO said.

Zelenskiy on Sunday again called for Western nations to beef up Ukraine’s air defences after weeks of Russian air strikes targeted the country’s energy network as a freezing winter settles in.

The conflict has killed tens of thousands of people and driven millions from their homes.

Zelenskiy told Ukrainians the armed forces were holding firm in the town of Bakhmut – scene of the fiercest fighting in the country for many weeks as Russia attempts to advance in eastern Ukraine’s Donetsk region.

“The battlefield in Bakhmut is critical,” he said. “We control the town even though the occupiers are doing everything so that no undamaged wall will remain standing.”

Denis Pushilin, Russian-installed administrator of the portion of the Donetsk region controlled by Moscow, said that Ukrainian forces shelled a hospital in the Donetsk city, killing one person and injuring several others.

Reuters could not independently verify the battlefield accounts.

Putin casts what he calls Russia’s “special military operation” as a watershed moment when Moscow finally stood up to a Western bloc, led by the United States, seeking to capitalize on the 1991 fall of the Soviet Union by destroying Russia.

Kyiv and the West say Putin has no justification for what they have decried as an imperial-style war of occupation that has resulted in Russia now controlling around a fifth of Ukraine.

Henry Kissinger, an architect of the Cold War policy of detente towards the Soviet Union as secretary of state in the 1970s, said the time was approaching for a negotiated peace.

“The time is approaching to build on the strategic changes which have already been accomplished and to integrate them into a new structure towards achieving peace through negotiation,” Kissinger wrote in The Spectator magazine.

Ukraine rejected the proposal, saying it amounted to appeasing the aggressor by sacrificing parts of Ukraine.

“All supporters of simple solutions should remember the obvious: any agreement with the devil – a bad peace at the expense of Ukrainian territories – will be a victory for Putin and a recipe for success for autocrats around the world,” Ukrainian presidential aide Mykhailo Podolyak said on Telegram.

Kremlin officials were not available for comment late on Sunday.

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