Militant Islamic students, responding to an appeal from Ayatollah Ruhollah Khomeini, agreed tonight to allow clergymen to hold Christmas services for the 50 American hostages at the U.S. Embassy in Tehran.

"We have heard what Imam Klomeini said," said a spokesman for the students, reached by telephone inside the occupied embassy. "It is right, and we accept it."

The response to Khomeini's call marked the first time the student leadership has agreed publicly to the idea of Christmas services for the hostages, who have been captive in the embassy since Nov. 4. Although it fell far short of U.S. demands for an international inspection panel, including a doctor, the student acceptence nevertheless seemed to be a goodwill gesture calculated to soften opposition to their refusal to release the Americans.

Simple acquiescene to Christmas celebrations seemed on the surface a tiny step. But, in the militant Tehran atmosphere, it was nevertheless taken as a concession and a sign of hope for further softening of the students' resolution to hold on to the hostages and put at least some of them on trial for espionage unless the deposed shah is returned to Iran.

The students acted after Khomeini, the spiritual and political leader of Iran's Islamic revolution, urged his Revolutionary Council to invite some clergymen into the embassy to conduct the services. His statement, read tonight on the state radio, in effect gave his blessing to a plan announced early this week by Foreign Minister Sadegh Ghothzadeh but left in doubt, pending a response from the students.

Observers had feared that the plan proposed by Ghothzadeh would be brushed aside by the student militants holding the embassy. An earlier suggestion by Ghothzadeh that some prisoners be released for Christmas was dismissed by the students.

This time, however, Ghothzadeh won the backing of Khomeini, whose name the students cite in emphasizing their determination to resist U.S. demands that the hostages b released. Observers said this could strengthen the hand of moderates in the undefined relations between the government and the militant students.

"It is necessary that you invite several responsible and committed clergymen so that the American Embassy can carry out religious ceremonies in complete peace," Khomeini's statement said.

He added that priority should go to blacks because of their "special stand against the crimes of America." Although he did not say so, the implication was that Khomeini was urging that the clergymen be American.

The student spokesman at the embassy said no clergymen have been decided on yet. He said only that the students want "the best" clergymen available.

The University of Kansas professors active in the anti-shah movement in the United States, Norman Forer and Clarence Dillingham, have been negotiating to win acceptance of several U.S. ministers and priests who, they say, have expressed willingness to fly to Tehran to concuct the ceremonies.

Ostensibly, their mission would be religious, to mark the holidays, but it would be likely to include a firsthand look of the prisoners as well, for a report on their condition.

Khomeini's statement said nothing about the hostages' release. Observers in past references to the captives.

The ayatollah referred to what he previously has called "a nest of spies" as simply "the embassy." In addition, the prisoners were called simply "Americans," without the references to spying contained in other recent statements from the Iranian leaders.

While such readings of Khomeini's statement may lend more importance to the ayatollah's words than they deserve, they nevertheless provide an indication of the atmosphere in which the students at the embassy act and make decisions. Hints of leniency from Khomeini could steer the students toward similar softening. By the same token, his stridet denunciations of the United States toughen the climate in the embassy compound.

The approval of Christmas services came as fresh disturbances were reported in the capital of Baluchistian. Hospital officials in Zehedan, about 1,100 miles southeast of Tehran near the Pakistani border, said five persons were killed and more than 20 injured in clashes between autonomy-minded Baluchi militamen and members of Khomeini's Revolutionary Guard.

It was the second consecutive day of fighting in Zahedan, where three were killed and more 40 injured yesterday in similar clashes. Khomeini's trouble-shooter for the restless minority leaders, former foreign minister Ibrahim Yazdi, announced a crease-fire agreement later into the night.

The population of Baluchistan, mostly Sunni Moslems, contests the sweeping powers granted to Khomeini's Shite Moslem leadership in the new constitution, which names the Shiite sect as Iran's official religion.

Along with the Kurds and other Iranian minorities, the Baluchis have posed a major challenge to Khomeini's ability to impose the central authority of his Islamic republic throughout Iran.

In another demonstration of this challenge the spiritual leader of Iran's 3 million Kurds confirmed today that his negotiating team "unanimously rejected" government proposals for increased regional autonomy in Kurdistan. Sheik Ezzedin Hosseni, in his statement from the Kurdish regional capital of Mahadabad, made it clear that Kurds were pressing for considerably more autonomy than the Tehran government seemed willing to grant. c

The government negotiators have been here several times, but they have never discussed the issue seriously" he said.