MOSCOW -- The Kremlin expects a swift start to U.S.-Russia talks on the confrontation over Ukraine after President Joe Biden and President Vladimir Putin both accused the other of military escalation in the region.
Putin on Wednesday called the video-link talks with Biden "open, substantive and constructive" amid Western fears that Russia's military buildup near Ukraine's border was a prelude to an invasion. In eastern Ukraine, Moscow-allied separatists have battled Kyiv's Western-allied forces since 2014.
But Putin also underscored the difficulties ahead: Russia's demand that Ukraine not be considered for NATO membership -- a stance that NATO officials have repeatedly made clear they will not agree to.
"We can continue this dialogue. It seems to me that's the main thing," Putin said.
In Washington, Biden said Wednesday that putting additional U.S. troops on the ground in Ukraine is "not on the table."
"I made very clear if in fact he invades Ukraine, there will be severe consequences, economic consequences like ones he's never seen," Biden told reporters as he left the White House en route to Kansas City, Mo. "His immediate response was he understood that."
Putin said Russia would shortly send Washington its proposals spelling out the security guarantees it wants.
"Russia will prepare its considerations literally within the next days, within a week, and we'll pass them on to the American side for consideration," he said.
Putin, speaking to journalists after talks with Greek Prime Minister Kyriakos Mitsotakis, dismissed a question about whether Russia planned to attack Ukraine as "provocative."
"We cannot help but be concerned about the prospects of Ukraine possibly joining NATO, because this would undoubtedly be followed by the placement of relevant military contingents, bases and weapons threatening us," Putin said.
"Russia pursues a peaceful foreign policy, but it has the right to ensure its security, as I have already said, in the medium and longer term," he added.
In Ukraine, top officials widely portrayed Tuesday's Biden-Putin talks as a path to ease the crisis. Ukrainian President Volodymyr Zelenskiy and others were also upbeat about Biden's pledges of support for Ukraine and warnings to Putin.
"I think that Ukraine's victory is that the United States has always supported Ukraine, our sovereignty, our independence," Zelenskiy said at a joint news conference after meeting with Croatian Prime Minister Andrej Plenkovic. Biden is due to brief Zelenskiy on the results of the talks on Thursday.
Ukraine's foreign minister, Dmytro Kuleba, said the talks had served to deter Russia.
Still, Ukraine has bolstered its forces near the Russian border and along front lines in the separatist regions, including sending more tanks and armored vehicles.
Ukraine's Defense Ministry said Wednesday that there had been six clashes with separatists over the previous 24 hours, with anti-government fighters reportedly using mortars, grenade launchers, large-caliber machine guns and small-caliber rifles. Shelling takes place regularly along the front line, according to the Defense Ministry.
On Monday, Zelenskiy visited troops in eastern Ukraine, where battles with Russian-backed rebel forces have claimed an estimated 14,000 lives in the nearly eight-year conflict. Last week, Zelenskiy directly challenged Moscow, saying Ukraine remains committed to "liberate" Crimea, the Black Sea peninsula annexed by Russia in 2014.
In Kyiv, however, as a freezing rain coated the streets and sidewalks, peoples' attention after Biden and Putin's two-hour conversation focused less on the military situation in the eastern part of the country, and more on the political maneuverings taking place around Ukraine as Zelenskiy faces one of the toughest challenges.
Russia, meanwhile, showed its willingness to confront NATO. Russia scrambled two Su-27 fighter jets to shadow two French military jets and a refueling plane in the Black Sea region. Russia also announced plans Wednesday to equip naval ships with Tsirkon hypersonic cruise missiles next year.
Russia's Foreign Ministry handed a formal protest note to the U.S. Embassy in Moscow on Wednesday complaining about "dangerous" actions of U.S. military aircrafts near Russia's Black Sea borders.
Kremlin spokesman Dmitry Peskov said follow-up talks from the Biden-Putin meeting were expected "very promptly." The gulf remains wide, however.
The White House readout emphasized Biden's warning of tough economic and other measures against Russia in the event of any Russian military escalation against Ukraine. Biden called for a return to diplomacy to resolve a seven-year war in eastern Ukraine.
The Kremlin readout called the conversation frank and businesslike but focused on Putin's complaints that NATO was "making dangerous attempts to conquer Ukrainian territory," and his demand for written guarantees ruling out Ukraine's membership of NATO or the deployment of missile systems in Ukraine.
Ukraine, sandwiched between Russia and NATO, has scaled up calls for a NATO membership action plan in recent months -- the first formal step to admission -- angering Russia. NATO has stonewalled, calling for concrete steps from Kyiv to address corruption.
Some in Ukraine were critical of efforts to resolve the conflict in the absence of Ukrainian officials directly involved.
"On the one hand, one would like to hope that this conversation will help prevent a worst-case scenario and de-escalate the situation. On the other hand, it is clear that any dialogue about Ukraine without Ukraine's participation will not be effective and sustainable," said Alyona Getmanchuk, director of the New Europe Center think tank in Kyiv.
She said Biden's willingness to respond to Putin's threats with meetings enabled the Russian leader to feed "the myth of the leaders of the two superpowers who decide the fate of the world."
The talks about Ukraine -- without Ukraine -- likely left Zelenskiy uncomfortable, she added.
"It is very important for him that Ukraine is respected in the world, that it is perceived as a full-fledged player in international politics," she said. "Of course, he would like Ukraine to be at the negotiating table."