Vladimir Putin has announced a “partial mobilisation” of Russia’s army reserves in a dramatic escalation of the war in Ukraine.

Speaking in an address to the Russian people on Wednesday morning, the president warned the West that Russia would use all the means at its disposal to protect its territory, saying: “It’s not a bluff.”

Defence minister Sergei Shoigu said later that 300,000 reservists would be called up to fight against Ukraine, from the 25 million available.

Speaking to those in “leading Nato states” who he claimed had talked of “the possibility of using nuclear weapons of mass destruction against Russia,” Mr Putin said: “I want to remind you that our country also has various means of destruction, and for separate components and more modern than those of NATO countries.