Russia has warned Poland against hosting any U.S. or NATO missile defense system in its territory. A Foreign Ministry spokesman says such a move would undermine the strategic balance and trigger a "corresponding" response from Moscow.
The Interfax news agency quotes ministry spokesman Mikhail Kamynin as saying Moscow could not rely solely on U.S. or NATO assurances that such systems would not be pointed at Russia.
Washington has repeatedly said the purpose of its planned missile defense system is to protect the United States and its allies from the threat of ballistic missiles from so-called "rogue" states such as Iran or North Korea.
Interfax quotes the Russian spokesman as saying Moscow would have to take measures to relieve any perceived threat. He did not offer details, but said the matter would be discussed in upcoming talks with Warsaw.
Poland, a former Soviet satellite, has become a key defense partner with the United States in the past decade.
Some information for this report was provided by AFP, AP and Reuters.