An overnight drone strike near the Ukrainian port of Odesa has sparked a massive fire and explosion, military officials said.
he attack came just hours after the United States vowed to take decisive action and promised “catastrophic consequences” if Russia uses nuclear weapons in Ukraine.
The air strike was the latest in a series of drone attacks on the key southern city in recent days.
The latest strike hit a military installation, detonating ammunition. Firefighters are struggling to contain the blaze, the Ukrainian military’s southern command said.
Concerns are growing that Russia may seek to escalate the conflict once it completes what Ukraine and the West see as illegal referendums in parts of Ukraine under its control.
The voting, which ends on Tuesday, took place after thousands of residents had already fled. Images have shown armed Russian troops going door-to-door to pressure Ukrainians into voting.
Russia is widely expected to declare the results in its favour, a step that could see Moscow annex the territory and give it the pretext to seek to defend it as its own territory under the Russian nuclear umbrella.
Jake Sullivan, the US national security adviser, made clear that Russia would pay a high price if it made good on veiled threats to use nuclear weapons in the conflict.
“If Russia crosses this line there will be catastrophic consequences for Russia. The United States will respond decisively,” he told NBC’s Meet the Press on Sunday.
Washington’s message has been more detailed in private conversations with their Russian counterparts, he said, without elaborating.
“So, the Russians understand where we are. We understand where we are. We are planning for every contingency,” Mr Sullivan said in separate comments to ABC’s This Week.
“And we will do what is necessary to deter Russia from taking this step.”
Elsewhere, a Russian rocket attack targeted a village in south-eastern Ukraine. The attack struck an unnamed village and the regional centre of Zaporizhzhia, regional military official Oleksandr Starukh said.
He posted pictures of damaged buildings and said unspecified infrastructure also had been damaged and fires were sparked by the attack.
Meanwhile, the first batches of Russian troops mobilised by Moscow have begun to arrive at military bases, the British military said.
In an online intelligence briefing, the UK Ministry of Defence said “many tens of thousands” had been called up. However, the Russians face challenges ahead.
“Unlike most Western armies, the Russian military provides low-level, initial training to soldiers within their designated operational units, rather than in dedicated training establishments,” the MoD said.
Under normal circumstances, two battalions deploy while a third remains behind to train. But in the Ukraine war, even the third battalion is deploying, weakening that training, the MoD added.