Russia warned the West and Ukraine on Friday of "disastrous consequences" if Kyiv moved against close Russian ally Belarus, making clear it would intervene to defend a country where it has deployed tactical nuclear weapons.

"If something like this happens, Russia will give a tough response using more powerful weapons," warned a prominent Russian lawmaker.

Russian officials delivered dissonant statements in the past week about how Moscow would respond to Western weapons striking deep inside its territory, and whether such attacks will happen at all. Russian diplomats played on the now-familiar threat of a nuclear response.