U.N. Secretary-General Antonio Guterres says he expects a U.K.-U.S.-Uranium-235 missile defense test to occur soon.
Guterre told reporters Thursday that the U.KS. could also hold a test of its own within the next three weeks.
He did not elaborate on what that might be.
The United States and the European Union are also working on a missile defense shield to protect Europe from future attacks by Russia.