British armed forces minister James Heappey said on Tuesday he did not think there was an imminent threat of escalation in the war in Ukraine, dismissing comments by Russian foreign minister Sergei Lavrov as bravado.

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 ... Everything we do is calibrated to avoid direct confrontation with Russia."

(Reporting by Kylie MacLellan, Editing by Paul Sandle)