Russia has said some units participating in military exercises will return to their bases, adding to glimmers of hope that the Kremlin may not be planning to invade Ukraine imminently.

But officials gave no details on where the troops were pulling back from, or how many, muddying efforts to determine the significance of the announcement, which buoyed world financial markets and the long-suffering ruble after weeks of escalation in Europe’s worst East-West standoff in decades.

It came a day after Russia’s foreign minister indicated the country was ready to keep talking about the security grievances that led to the Ukraine crisis — a gesture that changed the tenor after weeks of tensions.

But hours before the Russian Defence Ministry statement about the troops, a US defence official said Russian units were moving closer to the Ukrainian border, and western officials continued to warn that the Russian military could attack at any time, with some suggesting Wednesday as a possible invasion day.

Fears of an invasion grew from the fact that Russia has massed more than 130,000 troops near Ukraine. Moscow denies it has any such plans, despite placing troops on Ukraine’s borders to the north, south and east and launching massive military drills nearby.

US and other Nato allies have moved troops and military supplies towards Ukraine’s western flank, and promised more financial aid to the ex-Soviet nation.

Asked about the pullback, Russian foreign minister Sergei Lavrov stressed that Moscow holds military drills “on its own territory and according to its own plans, they start, go on and end as planned”.

He added that such drills always adhered to a schedule — regardless of “who thinks what and who gets hysterical about it, who is deploying real informational terrorism”.

Ukraine’s leaders expressed scepticism about the pullback.

“Russia constantly makes various statements,” foreign minister Dmytro Kuleba said. “That’s why we have the rule: we won’t believe when we hear, we’ll believe when we see. When we see troops pulling out, we’ll believe in de-escalation.”

European leaders have been scrambling to head off a new war on their continent, after several tense weeks left Europeans feeling caught between Russia and the US, and pushed up household energy prices because of Europe’s dependence on Russian gas.

German Chancellor Olaf Scholz met Russian President Vladimir Putin in Moscow on Tuesday, a day after sitting down with Ukraine’s leader in Kyiv.

In his opening remarks in the Kremlin, Mr Scholz addressed the Ukraine tensions but also noted Germany’s economic ties with Russia — which complicate western efforts to agree on how to punish Russia in case of an invasion.

Poland’s foreign minister Zbigniew Rau met Mr Lavrov in Moscow on Tuesday, and they discussed ways to use the Organisation for Security and Co-operation in Europe for more talks to ease tensions around Ukraine.

The day before, Mr Lavrov suggested more efforts at diplomacy in a made-for-TV meeting with Mr Putin that seemed designed to send a message to the world about the Russian leader’s position.

The foreign minister argued that Moscow should hold more talks, despite the West’s refusal to consider Russia’s main demands.

Moscow wants guarantees that Nato will not allow Ukraine and other former Soviet countries to join as members. It also wants the alliance to halt weapons deployments to Ukraine and roll back its forces from eastern Europe.

Mr Lavrov said possibilities for talks “are far from being exhausted”.

White House principal deputy press secretary Karine Jean-Pierre said: “The path for diplomacy remains available if Russia chooses to engage constructively. However, we are clear-eyed about the prospects of that, given the steps Russia is taking on the ground in plain sight.”

Ukraine’s foreign minister claimed credit for keeping the diplomatic path open — at least for now.

“We managed with our partners to restrain the Russian Federation from any further escalation. Today is already the middle of February and you can see that diplomacy continues to work,” Mr Kuleba said.

Ukrainian President Volodymyr Zelensky declared Wednesday would be a “day of national unity”, calling on the country to display the blue-and-yellow flag and sing the national anthem.