"We have repeatedly expressed readiness to jointly resist real threats," Putin said, Russian news agencies reported.

He named these common threats as "international terrorism, local armed conflicts (and) the danger of uncontrolled proliferation of weapons of mass destruction."

The strongman was speaking in the Black Sea resort of Sochi as a two-summit of NATO leaders opened on Tuesday in the British town of Watford.

He nevertheless used the occasion to lament the prickly relationship between Moscow and the military alliance, saying that despite Russia trying to suggest a "constructive" agenda, "since 2008 our cooperation has practically been curtailed."

He slammed NATO, which has angered Moscow by strengthening its presence in countries on Russia's borders, for "acting inappropriately not to say rudely, without taking into account Russia's interests."

Putin has never made any secret of his resentment at NATO expansion into former Soviet republics that he sees as belonging in Moscow's zone of influence.

Russia is "obliged to view NATO expansion, the development of its military infrastructure close to (its) borders as one of the potential threats to our country's security," he said.

He argued that the alliance is outdated, saying "bloc stereotypes of thinking of previous years cannot be an effective tool for seeking and taking effective decisions in the fast-changing conditions of the modern world."

While the Warsaw Pact on collective defence signed between the USSR and European allies no longer exists, NATO is still growing, he pointed out.

Nevertheless he assured the alliance that "I'm still counting on interests in shared security and a secure and peaceful future for the planet prevailing."