The Bush administration is hopeful that agreement can be reached next week with the Soviet Union on an elections process that could end the 12-year-old war in Afghanistan, officials said yesterday.

Senior administration officials said they expect the settlement formula will dominate negotiations on regional issues between Secretary of State James A. Baker III and Soviet Foreign Minister Eduard Shevardnadze in Irkutsk in central Siberia on Aug. 1-2.

Officials said they understand the Soviet-installed regime of President Najibullah in Kabul is willing to go along with the election plan.

The plan generally allows Najibullah to continue in office while elections are held, but denies him the advantages of incumbency by placing control of the secret police, defense, interior and information ministries in the hands of an interim authority, the officials said.

The interim authority, or commission, would be broadly supervised by the United Nations and the Islamic Council, which also would supervise the later elections.

Senior State Department officials are worried that the U.S.-backed mujaheddin rebels will not accept the proposal, but a department official said yesterday he was confident most of the rebels would go along.

Meanwhile yesterday, officials said the Senate Select Committee on Intelligence has voted to slash aid for the Afghan rebels, cutting an estimated $100 million. Sources say that the United States last year spent about $300 million in covert aid to the rebels.

The vote was said to be heavily in favor of the aid cut, but a leading supporter of the rebels, Sen. Gordon J. Humphrey (R-N.H.), said "there is plenty of time to decide the appropriate level of support" despite the reported cut. He pointed out that the House Permanent Select Committee on Intelligence will not act on the covert action portion of the intelligence budget until September.

Humphrey is not a member of the intelligence committee and he took pains to say he was not confirming the vote to slash aid.

Humphrey said he was told by a high-level State Department official in recent days that full funding for the rebels was important in light of the upcoming negotiations with the Soviets.

"I can't imagine a worse time in that context for this to be in the press," he said.

The principal obstacle between Moscow and Washington in working out a peace formula has been precisely how much power the Soviet-installed regime in Kabul would transfer to an interim organization in order to ensure that subsequent elections are free of coercion and intimidation.

The talks are part of a 12-day Baker trip to Asia beginning today that includes stops in Indonesia and Singapore and a first-ever visit by a senior American official to Mongolia, a former Soviet satellite now in the process of becoming a multiparty democracy.

The administration's policy shift on Cambodia last week, withdrawing support for a coalition fighting the Vietnamese-installed regime in Phnom Penh, is likely to be the dominant topic of conversation at Baker's first stop in Jakarta, where he will attend a meeting of the six-nation Association of Southeast Asian Nations (ASEAN) and countries allied with them.

The yearly conference, normally a routine affair, is likely to see the United States come under heavy attack both for changing its policy and for not consulting with ASEAN before doing so.

Staff writer George Lardner Jr. contributed to this report.