US Secretary of State Condoleezza Rice and her Czech counterpart Karel Schwarzenberg signed a treaty Tuesday under which the Czech Republic would host a radar base for a planned US missile defence system, reported dpa.
The top diplomats signed the deal, announced at the latest NATO summit, regardless of the hurdles it faces in the country's closely- divided parliament.
The centre-right cabinet of Prime Minister Mirek Topolanek is short several coalition votes and will likely have to win over leftist opposition lawmakers in order to see the deal ratified.
The Czech Republic has rolled ahead with the defence project of importance to the United States, while holding up a key European plan, the Lisbon Treaty designed at reforming the enlarged 27-member European Union.
Washington would also like to place 10 interceptor missiles in Poland as part of the system that it says is being developed against potential long-range missiles from so-called rogue states such as Iran.
The talks in Warsaw have been deadlocked over Polish demands for military aid but both sides say they remain committed to striking a deal.
In Prague, negotiators are yet to conclude talks on a lesser Status of Forces Agreement that defines rules for US troops to be stationed at the planned base in a military zone one hour south-west of Prague.
The plan to build US military bases in former Soviet satellites in central Europe, now members of NATO and the European Union, has irked Russia which has threatened to aim its missiles at the host countries.