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The Kremlin on Monday played down talk of a summit between Presidents Joe Biden and Vladimir Putin, dampening hopes that a US-Russia meeting could ease the crisis in Ukraine.
Dmitry Peskov, Mr Putin’s spokesman, said it was "premature to talk about any specific plans for organising any kind of summits" after France suggested it was close to holding such a meeting.
Early gains in European stock trading were wiped out after Mr Peskov’s comments.
The US said it was open to talks, as prolonged Russian drills in Belarus and murky developments on Russia's border with Ukraine heighten fears of military action.
Amid fears Russia will seek a pretext to invade, its security forces claimed on Monday that a border checkpoint had been destroyed by a projectile fired from Ukraine and that five saboteurs had been killed after crossing the border into Russia. Ukraine rejected both these claims.
In Britain, Prime Minister Boris Johnson’s spokesman said “elements of the Russian playbook” that could accompany an invasion were already “starting to play out in real time”.
There was further concern about Belarus, which borders Ukraine to the south, and which announced on Sunday that allied Russian troops were staying on its territory indefinitely.
“In the shadows of the Russian-Ukrainian conflict, we have seen more or less an annexation of Belarus, at least militarily, by the Russians,” said Austrian Foreign Minister Alexander Schallenberg.
“I have my doubts whether the Russians will ever pull out of Belarus again.”
EU foreign ministers, who were meeting in Brussels on Monday, called for Russia to return to the negotiating table after a flurry of calls by French President Emmanuel Macron aimed at brokering talks.
Mr Macron said the US and Russian leaders had agreed to talks in principle, although Mr Peskov cast doubt on that claim by saying that it was foreign ministers who were scheduled to meet. Mr Biden and Mr Putin last met in Geneva in June last year.
Moscow signalled that it is open to discussions on issues such as arms control, but has not hidden its frustration that the West will not discuss its central demand of refusing Ukraine admission to the Nato military alliance.
The fragile situation was worsened by claims and counterclaims about outbreaks of violence in eastern Ukraine, with shells fired across the line of contact between government forces and pro-Russian separatists.
The US and its allies have said that Russia could use a provocation such as this as grounds for moving its troops into Ukraine.
Germany’s Foreign Minister Annalena Baerbock described the situation as “very dicey” and told Russia not to play with the lives of people in eastern Ukraine.
“It is in your hands,” she said. “We are at the table every minute and every hour. We are waiting for you.”
The EU’s foreign policy chief Josep Borrell said on Monday that work was complete on preparing sanctions that Russia would face it if invades Ukraine – although he said he hoped they would not be needed.
While Europe has not said what these measures would involve, Denmark’s Foreign Minister Jeppe Kofod said they would be the “most devastating sanctions ever seen on Russia”.
“We are ready for a diplomatic solution. The problem is we don’t know where Putin and Russia will be,” Mr Kofod said.
Britain has separately lined up sanctions which it said would prevent Russian companies from raising money on London’s financial markets.
Western powers were facing a demand from Ukraine to bring in these sanctions immediately, with the Russian build-up on the country’s borders already taking its toll on the Ukrainian people and economy.
Ukraine’s President Volodymyr Zelenskyy said at the weekend that it would be too late to sanction Russia once it invades and asked western leaders: “What are you waiting for?”
His remarks won sympathy from Lithuania’s Foreign Minister Gabrielius Landsbergis, who said on Monday that Ukraine was “already under attack” and called on Europe to consider an immediate response.
The US said that imposing sanctions now would render them ineffective as a deterrent if Russia has further to fear from invading Ukraine.
Mr Schallenberg said Belarus could face separate sanctions if a Russian invasion was launched from there.
A German government spokesman said they were not aware that this was under consideration.