U.S. to Seek Phased N. Korea Curbs : Diplomacy: U.N. will be asked next week to approve sanctions ending in a full embargo if Pyongyang refuses to allow nuclear inspections.

The Clinton Administration said Friday that it will formally ask the U.N. Security Council next week to impose “phased” economic sanctions on North Korea, ending in a full embargo--and possibly a naval blockade--if Pyongyang does not respond.

U.S. officials said the draft resolution, expected on Tuesday, reflects an increasing receptivity by key members of the council--including Russia and, to some degree, China--after Pyongyang’s continuing refusal to allow international inspection of its nuclear facilities.

Diplomats said the 15-member body could vote on a sanctions resolution by the end of the month--relatively quickly by U.N. standards. Presumably, any embargo would take effect within a matter of days thereafter.

The firm move by the United States, which follows a week of preliminary discussions with South Korea, Japan and members of the Security Council, marks the first step toward formal disposition of the North Korean dispute--or possible military conflict, if Pyongyang chooses.

President Clinton met for an hour with his top national security advisers Friday to discuss the North Korean situation. The policy-makers met separately for three hours to hammer out details of the Administration strategy.

The U.S. intention was announced in Istanbul, Turkey, by Secretary of State Warren Christopher, who immediately flew home from a North Atlantic Treaty Organization meeting to help plan the U.S. moves.

“It’s time to move forward with the resolution,” he told reporters.

Although details of the U.S. proposal were still not firm, officials said it is expected to provide for a “phased” approach, calling for imposition of only modest economic restrictions at first, to be followed by a full embargo.

At least one official indicated that the sanctions might be enforced by a multinational naval blockade that would include U.S. warships.

There also could be extensive surveillance of shipping traffic in the area by U.S. radar aircraft.

U.S. officials said Russia now seems likely to support the general plan. They expressed hope that China will abstain--or at least refrain from vetoing the resolution--despite its current public stance arguing that the United Nations should try more diplomatic negotiations first.

The officials also said Japan and South Korea both are fully behind the plan.

The U.S. assessment appeared to be supported by a series of developments:

- In a move clearly designed to cement Moscow’s backing for the sanctions resolution, Christopher said Friday that the Administration will support a Russian proposal to call an international conference to discuss the North Korean situation.

But officials here cautioned that, while the U.S. proposal will voice Washington’s support for the idea of a conference, it will continue to press for passage of the sanctions resolution before such a meeting.

- In Vienna, the International Atomic Energy Agency, which oversees the nuclear inspection process, voted to withhold technical aid from North Korea because of its recalcitrance--and China abstained from the vote.

Diplomats read the development as a signal that Beijing may be softening its opposition to sanctions, at least enough to agree not to veto the U.S.-backed sanctions resolution when it comes before the Security Council.

- In response to the vote in Vienna, Pyongyang quickly renounced its obligations to cooperate with inspectors and expelled two international observers. This action, analysts suggested, could heighten support in the United Nations for a sanctions resolution.

Immediately after the White House meeting, top U.S. officials intensified diplomatic efforts to win support for the sanctions resolution, telephoning their counterparts in other countries.

Meanwhile, Peter Tarnoff, undersecretary of state for political affairs, arrived in South Korea to confer with leaders there. There still was no word whether he will also travel to Beijing.

The Administration’s new push on sanctions was accompanied by signs that it is beginning to bolster U.S. military readiness in the face of Pyongyang’s threats that an embargo might bring on a new war.

Although officials said the Pentagon has not ordered more ships or troops into the region, Defense Secretary William J. Perry has ordered the aircraft carrier Independence to remain within three sailing days of Korea, rather than steaming to Hawaii for an exercise.

Also Friday, former President Jimmy Carter conferred with White House National Security Adviser Anthony Lake. Carter plans a trip next week to confer with leaders of North and South Korea.

He was invited initially by North Korea--possibly because the Communist regime there is looking for a face-saving way to defuse the standoff, U.S. officials said.

South Korean leaders have reacted coolly to Carter’s impending visit, partly because they fear that it may detract from the effort to push through a sanctions resolution. As President in the late 1970s, Carter proposed pulling U.S. troops out of South Korea.

The dispute between the allies and North Korea involves Pyongyang’s refusal to permit international inspection teams to monitor and take samplings from its nuclear reactor at Yongbyon so the country’s claim that it has no nuclear weapons can be verified.

Although Pyongyang denies that it has any nuclear warheads, the CIA estimates that North Korea already has manufactured enough weapons-grade plutonium to make one or two nuclear bombs and says it could build another four or five by the end of this year.

The wrangling came to a head two weeks ago, when the IAEA reported that North Korea had removed enough of the fuel rods from its shut-down reactor to dash hopes of determining whether the country has any nuclear weapons--in violation of its obligation under an international treaty.

The agency’s action Friday--in which it denied North Korea about $250,000 in technical aid pledged to help it meet its international obligations--was mainly symbolic, important primarily because of the fact that China, North Korea’s longtime ally, abstained from the vote.

The decision to suspend the aid came on a vote of 28 to 1, with only Libya backing Pyongyang.

Hans Blix, the international agency’s director general, told reporters later that “it’s clear we have reached something of a watershed in our relations with North Korea.”

Pine reported from Washington and Wright from Istanbul. Times staff writer Stanley Meisler in Washington also contributed to this report.