Last minute hitches today prevented the scheduled transfer of American hostages held in the U.S. Embassy amid signs that government plans to remove them from the control of their militant Islamic captors may have foundered.

The plan's principal proponent, Foreign Minister Sadegh Ghotbzadeh, tonight appeared to have backed away from demanding the transfer. He said it would not be necessary if the captors allowed a U.N.-sponsored fact-finding commission to visit all of the estimated 50 hostages.

A statement issued tonight after a meeting of the 13-member Revolutionary Council basically reminded the captors that they had proposed the transfer themselves and must either stick to it or allow the commission visit.

The failure to transfer the hostages to government authority outside the embassy compound was the only undisputed fact emerging from a welter of contradictory statements in which the militants and Ghotbzadeh accused each other of lying.

Implicit in the day of charges and countercharges involving Ayatollah Ruhollah Khomeini, President Abol Hassan Bani-Sadr, Ghotbzadeh and the militant captors was the militants' apparent reluctance to give the hostages up and the council's reluctance to take responsibility for them.

In the latest episode of the 13-month old revolution's most bitter power struggle to date, the embassy captors throughout the day created obstacle after obstacle to prevent Ghotbzadeh from carrying out the transfer as planned.

At the heart of the confusion was yet another of the oracular thunderbolts that the 79-year-old Khomeini has frequently used to play one Iranian faction against another and remain unchallenged himself.

An early afternoon statement from his office here said Khomeini had remained "silent" about the hostage transfer. That indirectly backed up the militants' charges that neither the president nor the foreign minister was correct in claiming Khomeini has given his direct blessing for the operation.

On the surface, both contenders appeared to have called each other's bluff.

Ghotbzadeh had startled the militants Thursday in accepting their offer to hand over control of the hostages to the Revolutionary Council and thus to central government authority. They, in turn, had punctured his -- and the president's -- claims to having received Khomeini's direct support.

Symptomatic of the confusion was the militants' televised exhortation tonight requesting their followers not to demonstrate. Earlier the militants had staged demonstrations in front of the embassy to show their continuing support from the nation, but the numbers fell short of expectation.

Equally confusing were remarks by the foreign minister. Ghotbzadeh stepped out of an unscheduled meeting of the Revolutionary Council tonight and announced, "God willing, we will take over the hostages."

But less than two hours later, he said that if the militants keep the hostages but obey the Revolutionary Council's decision to let the U.N. commission visit all of them, "there is no problem."

Ghotbzadeh added that if the militants "want to obstruct that decision one way or another -- or do not comply with this decision -- the hostages will be taken over."

Minutes later on television the tants again reiterated their opposition to the commission's visiting all 50 of the hostages and their willingness to honor their pledge to hand the hostages to the Revolutionary Council rather than stand accused of running a "government within a government."

Much earlier in the day the militants explained their opposition to the transfer operation, which they had said could begin at 5 p.m., by rejecting Ghotbzadeh as the Revolutionary Council member charged with overseeing the operation.

At one point tonight, Ghotbzadeh told reporters he would step aside for another council member "as long as the students obey" what he called the council's "irrevocable" decision to have the commission visit the hostages.

Observers cautioned against predicting the outcome of the newest domestic crisis, or whether the five-man U.N. commission would agree to stay on in Tehran while the question was decided.

The commission already has stayed two weeks in Tehran, and flight plans for the return of its executive jet to Geneva have been filed for Monday.

At first glance, the militants and their allies among the right-wing clerical Islamic Republican Party appeared to have used Khomeini's indirect support to try to weaken Bani-Sadr and Ghotbzadeh.

Yet despite the militants' claims to represent the nation's will in opposing the Revolutionary Council, observers noted that no more than 3,000 Iranians demonstrated against Ghotbzadeh and his plan outside the embassy today.

For the most part, they appeared to be Tehran University students backing their embassy colleagues rather than the throngs of south Tehran's unemployed and slum-dwellers who in the past have answered demonstration calls in massive numbers.

Iranian television tonight said pro-militant demonstrations also took place in the provincial capitals of Tabriz and Shiraz, but there was no independent corroboration.

At the height of the tension this afternoon the militants' spokesman challenged the Revolutionary Council to send a member through an obviously hostile crowd.

"If the Revolutionary Council introduces its representative or representatives," a spokesman said, "the transfer of the hostages will be possible, but the reaction of the people here will show whether they agree or not."

Central to the militants' denunciation of the "compromisers" favoring the commission's visit, the hostages' transfer, or both, was their conviction that these were tactics designed to solve the U.S.-Iranian crisis and free the hostages.

Khomeini decreed two weeks ago that a solution to the hostage question must await formation of a new parliament to be elected later this month. The parliament is not expected to be able to deal with the hostage question until mid-April at the earliest.

The first inkling of trouble in the transfer plans came this morning when the captors denounced Ghotbzadeh's demands that they evacuate the 27-acre U.S. Embassy compound as well as allow the transfer of the hostages to government authorities.

The militants said they would deliver the hostages at 5 p.m. Saturday to the Revolutionary Council, but only on receipt of written orders.

By midmorning the captors had rejected Ghotbzadeh as the Revolutionary Council overseer for the operation and said he had lied in claiming to have had Khomeini's direct backing for the transfer.

But in the only sign of the day that the plan was proceeding according to shcedule, crews from state-run television entered the embassy grounds in apparent compliance with the militants' demands that the hostages be filmed and undergo medical checksbefore their transfer.

The main 2 p.m. radi news broadcast contained Khomeini's statement: "In some newspaper the transfer of the hostages to the Revolutionary Council has been attributed to the Imam," as Khomeini is called. "So we must say he is silent in this case and has given the right to parliament to decide about the hostages."

That statement did not actually constitute Khomeini's denunciation of the transfer plans, but it did put Bhotbzadeh and Bani-sadr on the defensive. t

Ban-Sadr countered by saying that in his Thursday morning meeting with Khomeini, which has been interpreted as approving the transfer plans, it was the ayatollah's son, Ahmad, who brought up the transfer plan originally formulated by the students themselves. Bani-Sadr indicated that Ahmad's action constituted Khomeini's approval.

Ghotbzadeh said Khomeini has "not issued a direct order to me" about approving the transfer plans, but had explicity entrusted the Revolutionary Council with dealing with the hostage question. In turn, the Revolutionary Council had empowered him to carry out the details and the transfer plans, Ghotbzadeh said.