The United States warned Russia on Sunday of a risk of "confrontation", before the start of talks under high tension in Geneva to try to defuse the explosive crisis around Ukraine and, beyond that, try to bring together visions seemingly irreconcilable on security in Europe.
A few hours earlier, Russia had ruled out any "concessions" for these negotiations. "This is completely excluded," Deputy Foreign Minister Sergei Ryabkov, who is to take part in the talks, told Russian news agencies.
"We are disappointed with the signals coming from Washington in recent days, but also from Brussels," he added.
The U.S. Secretary of State Antony Blinken said on CNN that there was "a path of dialogue and diplomacy to try to resolve some of these disputes and avoid confrontation" and that "the other path is one of confrontation and massive consequences for Russia if it renews its aggression of Ukraine.
"We are about to see which way President Putin is willing to go," he ruled.
This high-risk diplomatic week begins with a face-off between the deputy foreign ministers of the two rival powers, American Wendy Sherman and Russian Sergei Riabkov.
It will continue with a NATO-Russia meeting on Wednesday in Brussels, then a meeting on Thursday in Vienna of the Organization for Security and Co-operation in Europe (OSCE), to include Europeans who fear being marginalized.
A senior White House official said the Russians and Americans "would probably have an initial conversation on Sunday night," before holding their "main meeting on Monday" in Switzerland.
The West and Kiev accuse the Russians of massing nearly 100,000 troops on the Ukrainian border in preparation for a potential invasion, and have threatened Russian President Vladimir Putin with "massive" and unprecedented sanctions if he attacks the neighboring country again.
Measures that could go as far as cutting Russia off from the wheels of world finance or preventing the Nord Stream 2 gas pipeline dear to the Kremlin from becoming operational.
Objective: to show that they are more determined this time than in 2014, when Moscow annexed Ukraine's Crimea without the U.S.-European alliance being able to make it back down.
President Putin, who has met twice with his U.S. counterpart Joe Biden since the beginning of this new crisis, warned that new sanctions would be a "colossal mistake" and in turn threatened a "military and technical" response if "the very clearly aggressive line" of his rivals is maintained.
Above all, it imposed and obtained the extension of the dialogue to several of its demands, which were nevertheless seen as red lines by the West.
For the Kremlin claims that it is the West that is provoking Russia by stationing troops at its gates or arming Ukrainian soldiers fighting pro-Russian separatists in the Donbass, in eastern Ukraine.
He therefore calls for a major treaty excluding the entry of Ukraine into NATO and the withdrawal of American soldiers from the easternmost countries of the Atlantic Alliance.
However, not only do the Americans assure us that they are not ready to reduce their troops in Poland or in the Baltic States, but they also threaten to reinforce them if the Russians go on the offensive.
"The risk of a new conflict is real," warned Nato Secretary General Jens Stoltenberg on Friday.
"It is certainly part of their strategy to present a list of demands that are absolutely unacceptable and then claim that the other side is not playing the game and use that as a justification for aggression," said Antony Blinken.
For John Herbst, former US ambassador to Ukraine, the Russian military deployment is a "gigantic bluff" by Vladimir Putin to obtain concessions.
"As long as the Biden administration remains at least as firm as it is now," said this Atlantic Council think tank expert, "that should be enough to hold Putin back from invading Ukraine, but I wouldn't rule out a more limited operation."
Beyond the Ukrainian crisis, Washington hopes to take advantage of the talks to put US-Russian relations, at their lowest point since the end of the Cold War, back on track. And perhaps obtain progress on other issues, such as disarmament.
But from Paris to Berlin via Brussels, calls have multiplied to give a real place at the negotiating table to the countries of the Old Continent, and in particular the European Union - in the face of the Kremlin, which seems to want to favour the Russian-American tête-à-tête.
A test for Joe Biden's United States, which, despite promises of consultation, has scalded its European allies by giving the impression of going it alone on Afghanistan or the anti-China strategy.
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