British Prime Minister Boris Johnson has told Russian President Vladimir Putin that any incursion into Ukraine would be a tragic miscalculation as the United States prepares to send thousands of troops to Europe to bolster NATO allies.
Johnson and Putin spoke by phone on February 2 amid ongoing diplomatic efforts to ease tensions over Russia's military buildup near Ukraine.
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A spokesperson from Johnson's office said he "expressed his deep concern about Russia's current hostile activity on the Ukrainian border" and "emphasized the need to find a way forward which respects both Ukraine's territorial integrity and right to self-defense."
Johnson stressed that any further Russian incursion into Ukrainian territory would be "a tragic miscalculation," the spokesperson said.
A Kremlin statement said the "unwillingness of NATO to adequately respond” to Russian concerns "was noted" during the call.
After orchestrating the troop buildup, Russia in December demanded legally binding guarantees from the United States and NATO that Ukraine will never join the bloc, that NATO will halt the deployment of weapons systems near Russian borders, and that its forces will be rolled back from Eastern Europe.
NATO has said the demand on expansion is a nonstarter, saying it has an open-door policy that is not up for negotiation, and Washington has stressed that sovereign states have a right to choose their own military alliances.
The United States has told Russia it is prepared to hold talks on a reciprocal agreement over the deployment of ground-launched missiles or combat forces in Ukraine, according to documents published on February 2 by the Spanish newspaper El Pais.
Putin, who previously said Russia's demands had been "ignored," told Johnson that NATO was "hiding behind" its open-door policy, which the statement said "contradicts the fundamental principle of the indivisibility of security."
It added that Putin accused Ukraine of "chronic sabotage" of the Minsk agreements on resolving the ongoing conflict in eastern Ukraine, where more than 13,000 people have been killed.
The West has accused Russia of supplying military and financial help to the separatists, charges that Moscow rejects.
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Russia denies it is planning to invade despite surrounding its neighbor with an estimated 100,000 troops on the north, east, and south. It claims that the United States and NATO are the instigators, citing the Western response as evidence.
Earlier on February 2 the United States announced it will send about 3,000 troops to Poland, Romania, and Germany this week.
About 2,000 combat troops will deploy from the United States to Poland and Germany, while around 1,000 troops now based in Germany will move to Romania, Pentagon spokesman John Kirby said on February 2.
The troop deployments are "unmistakable signals to the world that we stand ready" to defend NATO allies and the troop movements are not the "sum total of deterrence actions" that the United States will take, Kirby said.
"It's important that we send a strong signal to Mr. Putin and, frankly, to the world that NATO matters to the United States and it matters to our allies," Kirby said at a news briefing, referring to Russian President Vladimir Putin.
He reiterated that the United States also remains open to continued diplomatic efforts to ease tensions caused by Russia's military buildup and does not believe that conflict is inevitable.
Moscow denounced the deployment as "destructive steps which increase military tension and reduce scope for political decisions."
Deputy Foreign Minister Aleksandr Grushko told the Interfax news agency the move will narrow the room for political decisions revolving around tensions in Ukraine "to the joy of the authorities in Kyiv."
The deployments are above and beyond the troops put on alert last month to be ready to deploy to Europe, Kirby said. They are under bilateral arrangements with Poland, Romania, and Germany and the troops deployed will remain under the U.S. chain of command, he added.
Kirby made clear that the moves were temporary but said there could be other troop movements inside Europe, including French forces expected to be sent to Romania. Kirby also said the Pentagon had not ruled out the possibility that additional forces will be moved from the United States.
Kirby also confirmed that documents published on February 2 by the Spanish newspaper El Pais are authentic.
U.S. President Joe Biden said his decision to deploy troops to Europe is consistent with what he has told Putin.
"As long as he is acting aggressively, we're going to make sure we can reassure our NATO allies and Eastern Europe that we're there and Article 5 is a sacred obligation," Biden told a CNN reporter. Article 5 of NATO's founding treaty says an attack against one ally shall be considered an attack against them all.
German Chancellor Olaf Scholz plans to travel to Moscow for a meeting with Putin.
"That is planned and will take place soon," Scholz said late on February 2 in an interview on public broadcaster ZDF without specifying a date.