'It's best not to mess with us .... Russia is one of the leading nuclear powers'
Russian president Vladimir Putin raised the spectre of nuclear war with the West last night as he defied international condemnation over his decision to send thousands of Russian troops and heavy armour into eastern Ukraine.
Accused by Europe and NATO of launching a full-scale invasion, the Russian president boasted to a group of Russian youngsters that "It's best not to mess with us".
In language not heard 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 alarm Western governments. Even during the Cold War, few Kremlin leaders resorted to direct mentions of Russia's nuclear arsenal. The Russian president made his remarks as European leaders prepared to hold an emergency summit today to discuss further sanctions.
It follows the appearance of what NATO believes is more than 1,000 regular Russian troops in eastern Ukraine.
The soldiers are believed to be the backbone of a counter-offensive in which pro-Kremlin rebels in eastern Ukraine have seized back swathes of territory from Ukrainian government forces in the past few days, dramatically turning the tide in the four-month conflict.
A major battle is now looming in the port city of Mariupol, where Ukrainian forces are bracing themselves for a full-scale assault by rebels backed by the Kremlin's forces.
The escalation in the conflict is the most serious since the pro-Russian uprising began, and has dashed Western hopes that sanctions had forced the Kremlin to abandon its support for the rebels.
"If it looks like a war, sounds like a war and kills like a war, it is a war," said Radoslaw Sikorski, Poland's foreign minister. "The situation is now out of control," added his German counterpart, Frank-Walter Steinmeier.
Speaking after an emergency summit yesterday to discuss the crisis, Anders Fogh Rasmussen, the NATO secretary-general, accused Russia of "hollow denials" over its role in the conflict. "Russian forces are engaged in direct military operations inside Ukraine," he said.
"Russia continues to supply the separatists with tanks, armoured vehicles, artillery and rocket launchers. Russia has fired on Ukraine from both Russian territory and within Ukraine itself."
At a summit in the Welsh city of Newport next week, NATO leaders will meet Petro Poroshenko, Ukraine's new president, to show what Mr Rasmussen described as "unwavering support".
Diplomatic sources have said that Ukraine will ask for a package of "non-lethal" aid, including thousands of new uniforms, helmets, body armour and communications gear. Ukrainian defence chiefs also want access to sophisticated US and NATO satellite images of Russian troop positions.
Arseny Yatseniuk, Ukraine's prime minister, said that his country would now seek to join NATO, although sources within the organisation said that it was out of the question in the foreseeable future. Any such move would oblige NATO to come to Ukraine's immediate defence against Russia. The new Russian incursions into Ukraine suggest the Kremlin has lost little of its appetite for the conflict, despite the international outrage that followed the downing of a Malaysian passenger jet in July.
As well as the regular Russian troops, NATO believes the Kremlin has sent in up to 100 battle tanks and 100 artillery pieces, as well as anti-tank weapons and shoulder-mounted missile launchers.
That, NATO officials have said, explains the sudden gains made by rebel forces, including the capture on Wednesday of the coastal town of Novoazovsk.
On Thursday night, Mr Putin appeared to give the rebels direct encouragement by describing them as the forces of "Novorossiya", or "New Russia".
The latest upsurge in the conflict is likely to reopen divisions within Europe over how to respond.
While Holland led calls for tougher sanctions yesterday, such a stance is likely to be hard for Italy and Germany, whose economies depend heavily on Russian gas. (© Daily Telegraph, London)