On his first visit to Warsaw, Obama also defended his "reset" of relations with Russia, a policy that has sometimes unnerved Poles wary of Moscow's resurgence and its efforts to roll back Western influence in former Soviet republics.

"Poland is one of our strongest and closest allies in the world and is a leader in Europe," Obama told a joint news conference with Polish Prime Minister Donald Tusk.

"What we want to do is to create an environment in this region in which peace and security are a given. That's not just good for this region. It is good for the United States of America. And we will always be there for Poland."

Obama and Tusk finalized a deal to establish a U.S aerial detachment in Poland from 2013 that will help to train Polish pilots in use of F-16 warplanes and C-130 transport planes.

"The size (of the detachment) is not large but it is a very meaningful gesture," Tusk said, alluding to Warsaw's long-standing desire for "American boots on the ground."

"What I have heard today gives me the feeling that we are working together to improve Poland's security."

Obama reiterated Poland's role in missile defense plans meant to counter the possible threat of short and medium-range ballistic missile attack from countries such as Iran. The plans envisage deploying SM-3 interceptors in Poland from 2018.