U.S. Plans to Extend Nuclear Test Ban : Arms: Clinton has not made final decision. Resumption would likely ignite fierce battle in Congress.

The Clinton Administration is preparing to extend the current U.S. moratorium on nuclear testing, with the proviso that the United States will not test nuclear weapons unless other nations do so first, U.S. officials said Tuesday.

The consensus position, which officials caution still has not been approved by President Clinton, reflects a realization by the Administration that it is unlikely to win congressional backing for a full resumption of the tests.

The current test ban, enacted by Congress 12 months ago, is scheduled to expire Thursday. If Clinton were to order a resumption of testing, he would have to notify lawmakers in advance, probably setting off a fierce battle on Capitol Hill, where sentiment against testing is high, particularly among Democrats.

A decision against resuming testing would be a setback for the Pentagon, which has been pressing for an end to the formal moratorium and for a program of nine nuclear tests that Congress had authorized before the moratorium was imposed. Those would include six tests involving U.S. weapons and three conducted for Britain, which has an agreement allowing it to use U.S. test sites when permitted under U.S. law.

Until recently, the Energy Department had supported the Pentagon proposal, and as late as four weeks ago the Administration had seemed ready to lift the ban entirely. But the Energy Department reversed itself and began vigorously opposing the Pentagon bid. Officials said the new position has been drafted by the National Security Council.

Opponents of the Pentagon’s push to end the moratorium have argued that resumption of testing by the United States would impede Washington’s efforts to persuade other countries to join the Nuclear Non-Proliferation Treaty.

Although most major industrial powers have signed the treaty, several Third World countries--most notably North Korea--are either not members now or are considering dropping out.

Those who support continuation of the moratorium also argue that Russia and three other former Soviet republics possessing inherited Soviet nuclear weapons might be alarmed by new U.S. testing.

Those familiar with the NSC plan said that Clinton most likely will couple it with a proposal to launch negotiations for a global ban on nuclear testing, to be unveiled at the same time.

Proponents said the advantage of the compromise plan would be that it would encourage other countries to join with the United States in forswearing nuclear testing, without undermining the Nuclear Non-Proliferation Treaty.

Conservatives have argued that the United States must continue nuclear testing if it is to remain the world leader in the field and hopes to ensure maximum safety of the weapons. But with the Cold War over, liberals in Congress have been able to muster majorities in favor of imposing or extending the moratorium. Officials said it was obvious that this year, the battle would be even tougher.

Also Tuesday, the State Department announced that the United States will resume talks with North Korea on July 14 on that country’s decision to consider dropping out of the treaty.