Russian President Vladimir Putin on Friday warned the west not to
President Vladimir Putin on Friday pointed to Russia's robust nuclear arsenal and sent out a terse warning to the West saying "don't mess with us" on Ukraine Reuters

Russian President Vladimir Putin on Friday brought back the memories of the Cold War era as he warned the West "not to mess with us" on Ukraine while curtly reminding them that Russia was one of the nuclear superpowers of the world.

The comment, which is noted to have raised the spectre of Russian nuclear war with the West, came as Putin remained resolute in defiance of international condemnation over his decision to send thousands of troops and heavy armour in aid of the pro-Moscow separatists in eastern Ukraine.

Having persistently been accused by US, Europe and NATO of launching a full-scale invasion into Ukraine, the astute Russian president boasted to a group of Russian youngsters that "it's best not to mess with us".

In a menacing tone, a first since the Cold War, he said to 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." The leader, resisting increasing pressure from the international community, seems to be clearly aiming to marshal public support for a military campaign that has invited a surge of stringent economic sanctions and international isolation.

Putin's comments, made during a talk with a pro-Kremlin youth camp on the banks of a lake outside Moscow, came a day after the US President warned of the increasing cost to Russians as its government deepens its surreptitious involvement in Ukraine's east, where pro-Russian rebels have almost fallen into the hands of aggressive government forces.

The increased tension and a clearly visible Russian anxiety comes after the Barack Obama on Thursday warned that stricter sanctions would be imposed in response to NATO releasing a set of satellite surveillance images showing Russian armoured columns crossing into south-eastern Ukraine.

"The images, captured in late August, depict Russian self-propelled artillery units moving in a convoy through the Ukrainian countryside and then preparing for action by establishing firming positions in the area of Krasnodon, Ukraine," NATO said in a press statement, before holding an emergency meeting on Friday.

Thursday onwards Ukrainian troops were battling a combined Russian and separatist forces in a new front located around the border town of Novoazovsk, east of Crimea on the Sea of Azov. This also came amid other reports that Russian troops were increasing surveillance from northern Crimea, the Ukrainian peninsula annexed by Moscow in March.