A senior State Department official on Tuesday said that the U.S. still is assessing how to implement President Donald Trump's order to resume nuclear weapons tests.
Undersecretary of State for Arms Control and International Security Thomas DiNanno told the Senate Foreign Relations Committee that no discussions have been held on conducting atmospheric nuclear tests.
The U.S. has not conducted an atmospheric nuclear weapons test since 1962.
DiNanno, however, did not exclude a resumption of underground nuclear weapons explosive tests, the last of which the U.S. conducted in 1992.
"We've made no decision specifically on how or what any testing program would look like," DiNanno said.
DiNanno's comments came in response to a question about how the directive that Trump issued in October to resume nuclear weapons tests was being implemented.
He reiterated U.S. charges that Russia and China have conducted explosive nuclear underground tests, which Moscow and Beijing deny, and some experts have challenged.
"This creates intolerable disadvantage to the United States not testing," he said.
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