Robert Simmons also said at a press conference in Baku that the NATO alliance has no plans for military action against the Islamic state after talks on Iran and regional security with Azerbaijani officials.

On Thursday, six major world powers agreed a proposal for new UN sanctions against Iran over its repeated refusal to suspend uranium enrichment -- a process that can be used to make nuclear fuel as well as atomic weapons.

Simmons also emphasised NATO's "open-door" policy to expansion, saying any country in Europe or the Caucasus was welcome to apply for membership. Two ex-Soviet republics, Georgia and Ukraine, are bidding to join the alliance.