U.S. experts just completed a weeklong inspection of a potential radar site near Prague that could be part of a U.S. missile defense system.
The five-member group conducted frequency measurements to avoid possible interference of the radar with existing equipment inside the Brdy military area, where the radar could be located.
"The data will be taken to the United States and evaluated for several weeks there," senior Czech Defense ministry official Radomir Jahoda said in a statement.
Jahoda said another group of U.S. experts should arrive in the Czech republic in mid-May, adding it would focus on hydrological, geological and climatic conditions in the area as well as logistics.
The U.S. made a formal request in January to put a radar base in the military area southwest of Prague as part of plans for a missile defense shield that Washington says would protect against a potential threat from Iran or North Korea.
The U.S. also wants neighboring Poland to place 10 interceptor missiles there as part of the system. The two former Soviet satellites are now NATO members.
Last week, the Czech government agreed to start negotiations with the United States on the possible hosting of the radar.
"There should be no Russian who goes to sleep without wondering if they're going to get their throat slit in the middle of the night,” Milley said