British Armed Forces Minister James Heappey on Tuesday downplayed Russian Foreign Minister Sergey Lavrov's comments on the possible use of nuclear weapons in the Ukraine war, calling them "bravado" and that there was no imminent threat of escalation in Ukraine.

Earlier Lavrov told the world not to underestimate the considerable risks of nuclear conflict, and said NATO's supply of weapons to Ukraine "in essence" meant that the Western alliance was engaged in a proxy war with Russia.

"Lavrov's trademark over the course of 15 years or so that he has been the Russian foreign secretary has been that sort of bravado. I don't think that right now there is an imminent threat of escalation," Heappey told BBC Television.

"What the West is doing to support its allies in Ukraine is very well calibrated."

Asked about the possibility of Russia using a tactical nuclear weapon, Heappey said he thought there was a "vanishingly small" possibility of that sort of escalation.

Heappey said that while NATO had been reinforcing its eastern flank, it was not providing military aid.

"That has not been a NATO endeavour, that is a community of donor nations who are all making bilateral contributions to the Ukrainians and that donor community extends well beyond the borders of NATO," he told BBC Radio.

"It suits the Kremlin's narrative to claim that they are somehow in a confrontation with NATO. They were saying that before the war even began, but that is nonsense and Lavrov knows it."

Moscow calls its actions a "special operation" to disarm Ukraine and protect it from fascists. Ukraine and the West say this is a false pretext for an unprovoked war of aggression by Russian President Vladimir Putin.

Heappey said it was completely legitimate for Ukraine to strike Russian logistics lines and fuel supplies and he acknowledged the weapons the international community was now providing had the range to be used in Russia.