The Clinton administration wants Russia to tighten control of nuclear weapons ingredients.
"It's not clear that this issue has been addressed at a very high level," State Department spokesman Michael McCurry said Tuesday after German authorities made their fourth seizure of weapons-quality plutonium since May.Russian officials have accused Germany of exaggerating the threat and jumping to the conclusion that the nuclear material was leaking from Russian warhead factories and nuclear laboratories.
"Clearly we are troubled by the recent seizures in Germany and want to know more about the accounting of this type of material," McCurry said.
He said the U.S. Embassy in Moscow was taking up the situation on an urgent basis with Russian technical experts and that Germany was sending an envoy to Moscow, as well.
"This is a matter that is serious and ought to be treated with a great deal of urgency by all governments that are in a position to help," McCurry said.