After talks with Czech Republic Prime Minister Mirek Topolanek in Prague Thursday, Tusk said a major issue in negotiations with U.S. officials would be increased security in both countries, Polish Radio reported.

Tusk and Topolanek say it is more important what their countries gain with the deployment of the missile shield than to complete talks within a short period.

The radio report quoted Polish Defense Minister Bogdan Klich as saying this week Poland would not accept the U.S. missile shield base unless the United States increased Polish air defense.

The U.S. plan to deploy interceptor missiles in Poland and a radar site in the Czech Republic is strongly opposed by Moscow, which claims the missile defense system is aimed against Russia.

Washington says the anti-missile shield is to defend against missiles fired from such countries as Iran or North Korea.