STOCKHOLM (Reuters) – Britain’s defense minister called on President Vladimir Putin on Thursday to pull back from the brink over Ukraine and warned that Russia would face long-term severe consequences if its forces invaded its neighbor.

“Any action by Russia to threaten the sovereignty of Ukraine would not only have severe consequences – they’d have long lasting consequences for Russia,” Defense Secretary Ben Wallace said.

Wallace called on Kremlin chief Putin to step back from any such moves which he said could trigger a deadly civil war on the edge of Europe.

“I would just urge him to think again: I don’t think Russia wants those consequences,” Wallace said. “I don’t want to see a civil war or a war at the edge of Europe.”

U.S. intelligence assesses that Russia could be planning a multi-front offensive on Ukraine as early as next year, involving up to 175,000 troops.

The Kremlin denies it plans to invade and says the West is gripped by Russophobia. Moscow says the expansion of NATO threatens Russia and has contravened assurances given to it as the Soviet Union collapsed in 1991.

Wallace said that Russian talk of NATO encirclement was nonsense.

“Only 6% of the Russian land border is bordered by NATO countries – that’s hardly being surrounded by NATO,” Wallace said.

“NATO is a defensive alliance – it is in our articles of establishment. It is only there to defend itself and its members if it were to be attacked.”

Wallace said it was up to sovereign states and NATO members if they joined NATO – not Russia.

(Reporting by Guy Faulconbridge; Editing by Kate Holton)