Nato has just three years to prepare for an attack by Russia, Poland’s national security agency has said.

Jacek Siewiera, head of the National Security Bureau, said a German think tank’s estimate that Russia could directly attack the West in “as little as six to 10 years” was incorrect.

“If we want to avoid war, Nato countries on the eastern flank should adopt a shorter, three-year time period to prepare for confrontation,” he told the Nasz Dziennik newspaper.

The German Council on Foreign Relations warned in a report last month that Russia could invade a Nato country in six years’ time and that Germany’s armed forces needed a “quantum leap” to be ready for it.

Mr Siewiera added that Poland needs to increase the size of its army in preparation for a potential attack.

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