Secretary of the Russian Security Council Nikolai Patrushev, Oct. 17, 2012 (photo: Office of the President of Russia)

A key security adviser to Russian president Vladimir Putin has accused the US of seeking to drag Russia directly into war in Ukraine through a possible plan to arm Kiev, underlining the seriousness with which Moscow would greet such a move.

“The Americans are trying to draw the Russian Federation into an interstate military conflict, to achieve regime change through the events in Ukraine and to ultimately dismember our country,” said Nikolai Patrushev, head of the Kremlin’s security council.

The warning represented Moscow’s first high-level comments on the intensifying debate in Washington about supplying lethal weapons to a Ukrainian military at war with Russia-backed separatists.

The start of such arms supplies would be “one more confirmation that the US is a direct participant in the conflict,” Mr Patrushev added, warning that if Washington took this step, the conflict would “escalate only further“.

Mr Patrushev is one of Mr Putin’s closest associates — a former head of the FSB intelligence agency that succeeded the KGB, and one of the security officials with whose help the president runs the country….

At the same time, Russia has increased the frequency of what foreign military officials call “nuclear signalling” – testing missiles and the readiness of its nuclear arsenal infrastructure. “It is a fact that any theoretical conflict between Russia and Nato would have to turn nuclear very quickly, because that’s the only sphere where they can still match Nato,” said one foreign defence official in Moscow….