U.S. to Press U.N. for Sanctions on N. Korea - Diplomacy: Atomic agency says it cannot determine if reactor fuel was diverted in 1989 for nuclear weapons.

The International Atomic Energy Agency declared on Thursday that its ability to tell whether North Korea diverted reactor fuel to make nuclear weapons in 1989 has been “seriously eroded,” and President Clinton said the United States would press the United Nations to enact sanctions.

While the President is traveling in Europe, special U.S. negotiator Robert L. Gallucci is scheduled to meet with South Korean and Japanese envoys today and Saturday to hammer out a proposal on sanctions, officials said.

But there were fresh indications the effort to punish Pyongang may prove difficult. Both China and Russia repeated Thursday that, despite North Korea’s actions, they are not yet prepared to support a resolution imposing economic sanctions.

Thursday’s decision ends 15 months of maneuvering between the U.N.-affiliated atomic energy agency and North Korea. Pyongyang initially invited the agency’s inspectors to its Yongbyon reactor, then barred them entirely and finally allowed them access only to part of the site.

As a result, while the inspectors have confirmed that North Korea is not now diverting spent fuel rods to make nuclear weapons, they have been unable to say whether it did so during an earlier reactor shutdown in 1989.

That issue is important because U.S. intelligence agencies suspect that North Korea may have used the spent fuel to build one--or possibly two--nuclear weapons. If North Korea does have a nuclear bomb, it could threaten Japan and the rest of Asia.

At the same time, North Korea has warned repeatedly that it would regard the imposition of sanctions as an act of war, raising fears in some quarters that the North might initiate military action against South Korea.

U.S. military authorities said Thursday that they have not put American forces in the region on alert, partly to avoid any actions that might be deemed provocative. But the Pentagon is considering scaling back a fleet exercise to leave ships available in case of hostilities, they said.

The atmosphere at the United Nations was increasingly tense. The Security Council is expected to meet informally to discuss the issue as early as today.

But diplomats cautioned that the 15-nation body likely will not get around to firm action until late next week after members reach agreement on a measure that can be passed by a clear majority.

It was not immediately clear just how much the continuing reluctance of China and Russia to go along with sanctions would hurt the American effort in the United Nations. Russian President Boris N. Yeltsin told reporters in Moscow that imposing sanctions now would be premature. But he warned that “if North Korea takes a stubborn stance,” eventually “we will be forced, step by step . . , to resort to international sanctions.”

In Beijing, Chinese spokesman Shen Guofang took a similar tack, warning that resorting to sanctions now “might sharpen the confrontation.” But neither Russia nor China indicated whether they would veto a Security Council resolution imposing sanctions.

A senior American official traveling with Clinton in Rome said the President was trying to arrange a telephone conversation with Yeltsin to discuss the issue. The official also conceded that Washington is uncertain how quickly or how forcefully it could get the Security Council to act. That “will depend on the nature of discussions that we’re engaged in,” he said. “We simply will have to see.”

The job facing the international inspectors has been complex. The standard method by which the agency’s experts tell whether a country is diverting spent nuclear fuel for weapons is to test fuel rods in a reactor.

Telling whether spent fuel had been diverted in previous years--such as in 1989, when analysts believe North Korea may have begun making a bomb--is more difficult.

To do so, the inspectors must measure how fuel rods in various parts of the reactor have been used up.

The task was complicated substantially a few weeks ago when Pyongyang announced to the West’s surprise that it would begin shutting down its reactor immediately and start removing the spent fuel rods well ahead of schedule--much faster than the atomic energy agency had expected.

North Korea removed the rods at such a rapid pace that the inspectors were unable to determine if any of the spent fuel had been diverted during the 1989 shutdown--leaving the West still uncertain whether Pyongyang has a bomb.

Hans Blix, director of the International Atomic Energy Agency, said in a letter Thursday that the agency still might be able to find clues to what North Korea did in 1989 by testing materials at two remote waste sites. But Pyongyang refused inspectors access to those areas 15 months ago.

As a result, Blix said, the ability of the Vienna-based agency to measure the fuel rods in accordance with international standards--and to verify the accuracy of North Korea’s claim that it does not have nuclear weapons--has been “seriously eroded” and essentially has been lost.

Blix is expected to travel to New York to confer with U.N. officials as early as today. But officials said that the agency’s board of governors is scheduled to meet in Vienna on Monday and he may delay the trip until Tuesday.

The Clinton Administration lost no time in beginning its push for sanctions. Senior officials were busy contacting their counterparts in Britain, France, China and Russia--the other permanent Security Council members--to discuss the timing of the move.

Washington hoped to work simultaneously with South Korea and Japan this weekend and to discuss the issue with America’s major European allies while Clinton is overseas. Officials said that debate in the Security Council on the issue could come on Monday.

Times staff writers John Broder in Rome, Carey Goldberg in Moscow and Rone Tempest in Beijing contributed to this report.