U.S. Secretary of State Condoleezza Rice and Czech Foreign Minister Karel Schwarzenberg signed an agreement Tuesday on the deployment of a missile-tracking radar on Czech soil.
The two countries also need to agree terms and conditions covering the deployment of military personnel in the Czech Republic before they can sign the Status of Forces Agreement (SOFA).
Vaclav Klaus said if the country's parliament ratifies the treaty, he will sign it into law "without a moment's hesitation."
First Deputy Foreign Minister Tomas Pojar has said the Czech parliament could ratify the deal by the end of the current year.
As part of the missile defense system, the United States plans to place interceptor missiles in Poland, but talks with Warsaw have stalled.
The plans are fiercely opposed by Russia, which sees them as a threat to its national security and the international nuclear deterrence system.
Schwarzenberg earlier said that after Russia's lease of Azerbaijan's Gabala radar station expires, its possible use could become a subject for NATO discussions.
Russia has offered the United States the use of its radar stations in Armavir in southern Russia and Gabala in Azerbaijan as alternatives, but Washington said they could only be used as "supplements," if at all.
Russian President Dmitry Medvedev has vowed to retaliate over the U.S. missile shield plans in Central Europe.
He also said Moscow was concerned by the signing of the Czech-U.S. missile treaty, but added that Russia was ready for further talks.
