Tension soared over Russia’s mass military deployments near Ukraine, with President Joe Biden putting 8,500 U.S. troops on alert and consulting Washington’s European allies on steps to be taken as Moscow gave no indication it was willing to pull back its forces.

Moscow blamed the United States and NATO for the heightened unease after the Alliance said it was bolstering defences in eastern Europe. Kremlin spokesman Dmitry Peskov said the West was engaging in “information hysteria”.

“This is not happening because of what we, Russia, are doing. This is all happening because of what NATO and the U.S. are doing and due to the information they are spreading,” he said.

Tensions had seemed to be ebbing somewhat late last week when both Russia and the United States appeared conciliatory after a day of talks between the Kremlin’s veteran foreign minister, Sergei Lavrov, and U.S. Secretary of State Antony Blinken.

Lavrov described the hastily-arranged talks in Geneva as “a useful, honest discussion,” while Blinken said they were “direct, businesslike” without polemics.

“I hope the emotions subside a bit,” Lavrov said.

But developments through the weekend pushed anxiety to new levels.

Western and Ukrainian estimates put the number of troops deployed near Ukraine’s border at about 100,000. Troops have been redirected to the area from as far away as Russia’s far east and a large contingent has also been dispatched to Belarus, Russia’s ally on its western frontier, for joint exercises.

Russia denies any intention of invading Ukraine.

But Moscow demands “guarantees” which amount to the adoption of new security arrangements in Europe, including an undertaking that NATO will expand no further and Ukraine will never be allowed to join. The United States and NATO have described those demands as non-starters, but Blinken said after last week’s meeting with Lavrov that Washington would submit written replies to Moscow’s proposals.

Nearly eight years after annexing Crimea and fomenting a separatist rebellion in eastern Ukraine, Russia denounces its ex-Soviet neighbour – and its president Volodymyr Zelensky – as a vassal of the United States and says any notion of Ukrainian NATO membership poses an existential threat.

No decision yet on troop deployment

Pentagon press secretary John Kirby said 8,500 U.S. troops had been placed on high alert to deploy at short notice. The Pentagon said no decision had yet been made on whether to deploy troops – that would be subject to the Alliance deciding to activate its rapid-reaction force.

There were no plans to send troops to Ukraine.

“It’s very clear the Russians have no intention right now of de-escalating,” Kirby told a news conference. “What this is about, though, is reassurance to our NATO allies.”

NATO said it was boosting its “deterrence” in the Baltic Sea area, with deployments already mostly announced by individual countries. Denmark, Spain, Bulgaria were dispatching ships or aircraft to Eastern Europe. France said it was ready to send troops to Romania and the Netherlands pledged to deploy fighter jets by April.

Biden last week said he believed Russia would stage an invasion of some sort in Ukraine, but created a measure of confusion by initially distinguishing between an invasion and a smaller incursion and saying the reaction in Western countries might not be uniform. He and other officials later offered clarification, saying any incursion amounted to an invasion.

The president spent much of the weekend being briefed on various options by senior defence officials. The decision announced on Monday to place troops on alert amounted to something of a turnaround from a previously cautious U.S. approach.

The White House said the president and European leaders “reiterated their continued concern about the Russian military build-up on Ukraine’s borders” during an 80-minute video conference and discussed “preparations to impose massive consequences and severe economic costs on Russia for such actions as well as to reinforce security on NATO’s eastern flank.”

“Total unanimity”: Biden

“I had a very, very, very good meeting. Total unanimity with all the European leaders,” Biden said.

Attending the call were leaders of Britain, France, Germany, Italy and Poland as well as the European Union and NATO.

In the lead-up to the latest consultations, U.S. weapons previously earmarked for Ukraine began arriving in Kyiv. Anti-tank weapons had arrived last week from Britain.

And at the weekend, Britain accused Russia of planning to install a pro-Russian government in Kyiv and even identified a former member of Ukraine’s parliament, Yevhen Muraev, as the figure identified to head such an administration. Muraev, an opponent of President Zelensky, but not especially close to Moscow, dismissed the allegation, as did Russia.

British Prime Minister Boris Johnson said there were 60 Russian battle groups on the borders of Ukraine, deployed with the intention of staging “a lightning war that could take out Kyiv”.

Johnson said any invasion is “going to be a painful, violent and bloody business”.

It was only two weeks ago that Russia, the United States and NATO were engaged in three rounds of talks in three European cities, packed into a four-day period. The Russian demand for “security guarantees” was the focal point,

Russian negotiators pronounced those talks to be a failure, with one saying they pushed relations into a “dead end” – prompting another day of exchanges last week between Blinken and Lavrov.

Russia seized Crimea in 2014 after mass protests in Kyiv drove out the country’s Moscow-friendly president from office and soon after, Russian proxies took control of large swathes of eastern Ukraine’s Donbas region. More than 13,000 have died in nearly eight years of conflict.

Diplomatic efforts have made no progress in settling the dispute over Donbas and Putin refuses any direct talks on the issue with Zelensky.

French President Emmanuel Macron last week called for the resumption of the “Normandy Format” – bringing together France, Germany, Russia and Ukraine – to tackle the Donbas issue. Moscow has rejected any new Normandy meeting, clearly preferring to deal directly with Washington.

Zelensky came to power in 2019 with a pledge to clinch a deal with Moscow on returning Donbas to Kyiv’s control, but now says any solution depends on Ukraine joining NATO.

NATO issued a promise at a 2008 summit that Ukraine – and ex-Soviet Georgia — would “one day” join the Alliance, but no date was set and the prospect looks remote.

Germany’s new Chancellor Olaf Scholz, who has been reluctant to offer arms and military assistance to Kyiv in the same manner of other NATO members, said that issue – and Russia’s demands — were irrelevant, with no immediate plans for the Alliance to expand.

“The accession of further countries from Eastern Europe to NATO is currently not on the agenda at all.,” Scholz told the Suddeutsche Zeitung. “What is the point of the Russian demand? There can be no such guarantee.”