The plans have proved the main bone of contention in relations between the U.S. and Russia, and were the focus of two meetings between the countries' top diplomats and defense chiefs last October and in March this year.
"Of course, we do not much like the idea [of a missile shield], we believe it's redundant, and we see in its implementation certain threats to Russian interests; we have openly and unambiguously told our partners about this," Medvedev told Chinese media the day before his visit to China.
Washington wants to place 10 missile interceptors in Poland and a radar station in the neighboring Czech Republic, purportedly to counter a missile threat from Iran and other "rogue" states. Russia has fiercely opposed the plans, saying the European shield would destroy the strategic balance of forces and threaten Russia's national interests.
Russia is "naturally ready to continue talks on all tracks... with our European partners, and with our American partners, including on these issues," the Russian leader said.
Former president Vladimir Putin proposed last year setting up missile defense information exchange centers in Moscow and Brussels. Russia has also offered the U.S. use of radar stations at Armavir in south Russia and Gabala in Azerbaijan, as alternatives to the missile shield deployment in Central Europe.