Vladimir Putin: Don't mess with nuclear-armed Russia

Vladimir Putin raised the spectre of nuclear war with the West on Friday as he defied international condemnation over his decision to send thousands of Russian troops and heavy armour into Ukraine.

Accused by Europe and Nato of launching a full-scale invasion of eastern Ukraine, the Russian leader boasted to a group of Russian youngsters that "It's best not to mess with us."

In language not seen since the height of the Cold War, he told his audience: "Thank God, I think no one is thinking of unleashing a large-scale conflict with Russia. I want to remind you that Russia is one of the leading nuclear powers."

Mr Putin's comments, made during a visit to a pro-Kremlin youth camp on the banks of a lake outside Moscow, will horrify Western governments as they try to bring Russia into check. Even during the height of Cold War hostilities, few Kremlin leaders ever resorted to the direct mentions of Russia's nuclear arsenal.

He made his remarks as European leaders prepare to gather tomorrow for an emergency summit to discuss further sanctions on Moscow over the appearance in the last few days of more than 1,000 regular Russian troops in eastern Ukraine.