Nato has said it still sees no sign Russia is pulling back forces from the Ukrainian border, despite claims by Moscow that its troops have begun returning to their bases.

Alliance defence ministers meeting in Brussels said they remained “gravely concerned” by the Russian military build-up and again urged the Kremlin to revert to the “path of diplomacy” in line with its international commitments.

General secretary Jens Stoltenberg said they were now considering establishing new battlegroups in central, eastern and south-eastern Europe to counter the threat from Moscow, which he described as “the new normal”.

Britain has previously offered to send RAF jets and warships to the region to strengthen the alliance presence there.

In a joint statement, the defence ministers said: “We are gravely concerned by the very large-scale, unprovoked and unjustified Russian military build-up in and around Ukraine and in Belarus.

“We urge Russia, in the strongest possible terms, to choose the path of diplomacy, and to immediately reverse its build-up and withdraw its forces from Ukraine in accordance with its international obligations and commitments.”

Mr Stoltenberg said that while they welcomed signs that Russia was prepared to continue with diplomacy, they had not seen any signs of de-escalation on the ground.

“What we see today is that Russia maintains a massive invasion force ready to attack, with high-end capabilities from Crimea to Belarus. This is the biggest concentration of forces in Europe since the Cold War,” he said.

“Moscow has made it clear that it is prepared to contest the fundamental principles that have underpinned our security for decades, and to do so by using force. I regret to say that this is the new normal in Europe.”