Gorbachev Proposes to Let U.S. Inspect Nuclear Sites

Soviet leader Mikhail S. Gorbachev, in a letter to President Reagan, has offered to let American inspectors visit Soviet underground nuclear test sites, a U.S. official said today.

But Gorbachev made the proposal conditional on U.S. acceptance of a moratorium on further tests. The White House, although not referring to the letter, rejected such a link--at least for now.

In the letter, Gorbachev also urged Reagan to approve a resumption of U.S.-Soviet talks next month on a treaty to ban all such tests, said the U.S. official, who demanded anonymity.

The offer to permit U.S. inspectors at Soviet test sites to clear up “ambiguities” has the potential of giving the lagging arms control process a major push forward in the aftermath of the Reagan-Gorbachev summit meeting.

The official said the offer is conditional on Reagan’s acceptance of a moratorium on further tests. A self-imposed Soviet ban will expire Jan. 1.

White House spokesman Larry Speakes welcomed any advancement that would lead to reciprocal visits to nuclear testing sites but brushed aside a connection to a ban on testing.

“They could come tomorrow if they like,” Speakes said. “We will be glad to continue to talk to them about on-site inspections, but as far as a moratorium . . . we would not agree to it at this time.”

A U.S. nuclear test, due to be conducted today, was postponed, but weather was officially blamed, and there was no indication that the action was related to the Soviet proposal.

The official said he did not know what the President’s response will be to Gorbachev. Charles Redman, a State Department spokesman, said the two sides had “confidential exchanges” but he refused to say anything about the letter.