Fifty American hostages in the occupied U.S. Embassy in Tehran entered their eighth week of captivity today and preparations to give them the Christmas celebration ordered by Iran's Islamic leader.

There were two separate reports -- one from a Roman Catholic priest who visited the embassy and the other from a French parliamentary delegation -- that at least some of the hostages could soon be released. Neither report was confirmed by the students holding the hostages and observers recalled that several similar predictions have proved unfounded in the past.

The students, reached inside the embassy by telephone, also denied a report circulated here, attributed to a source who entered the embassy today, that the hostages have been moved outside the embassy to other buildings in Tehran. There have been previous suggestions, including some from Washington, that hostages have been sneaked out of the embassy compound, but these have never been confirmed.

In another development, Sean McBride, former head of Amnesty International, was in contact with ruling Revolutionary Council members today in connection with the proposal of Foreign Minister Sadegh Ghotbzadeh -- which has been accepted by the country's leader, Ayatollah Ruhollah Khomeini -- for an international tribunal.

This body, which Ghotbzadeh has likened to a "grand jury," would weigh the students' and Khomeini's charges of U.S. crimes in Iran from the time the deposed shah took power as well as the alleged crimes of the shah himself.

McBride declined to say whether he would serve on such a panel, but he confirmed that the suggestion is the subject of his two days of discussions here with Iranian leaders.

Meanwhile, Washington Post correspondent Michael Weisskopf reported from Zahedan, the capital of troubled Baluchistan-Sistan Province, that calm returned to the town today after three days of fighting between two ethnic groups.

A large convoy of five Army tanks, eight trucks, and two armored personnel carriers with scores of Iranian national soldiers patrolled the city early this morning, Weisskopf reported. Shops closed for most of yesterday reopened today and the streets once again filled with residents, he said.

Since Thursday, 12 people have been killed and about 80 wounded in armed clashes between Baluschis and Sistanis, who represent different sects of the Islamic faith. The fighting had antigovernment overtones, with Baluchis contending that the smaller Sistani population had allied with revolutionary militiamen assigned to the southeast provincial capital by Khomeini.

In Tehran, the reports of release or transfer of hostages coincided with speculation that the Revolutionary Council has proposed to Khomeini that the students be ordered to free at least those hostages against whom there is no suspicion of spying -- the charge most often leveled against the Americans by their captors.

The council met for four hours with Khomeini at his headquartdrs in the holy city of Qom last Thursday night and promised a major announcement soon. Council members have since confirmed that the question of releasing some hostages was among the subjects discussed, but no announcement has been made.

Any decision to release hostages would have to come from Khomeini, the Iranian revolution's spiritual and political leader. The Islamic students holding the embassy appear to take orders only from him and have balked at suggestions even from council members that innocent hostages be freed.

It was Khomeini's direct order Friday that prompted the students to agree to allow American clergymen inside the embassy to conduct Christmas services for the hostages. Three American clergymen -- the Rev. William Sloane Coffin of Riverside Church in New York; the Rev. William Howard, president of the National Council of Churches; and Auxiliary Bishop Thomas J. Gumbleton of Detroit, representing the U.S. Catholic Conference -- are scheduled to fly into Tehran on Christmas Eve for the special observances.

[In Algiers, the Algerian news agency announced that Iran had also invited the Roman Catholic archbishop of Algiers, French-born Cardinal Leon Duval, to spend Christmas with the hostages. Invitations had also gone to former archbishop Hilarion Capucci of Jerusalem and two South American priests, the agency added, according to a Reuter dispatch.]

Approximately half a million Christmas cards have been delivered to the embassy. Student spokesmen say the hostages have received them, along with gifts and a Christmas tree delivered by the Rev. Alfredo Picchioni, a Persian-speaking Italian priest here, and diplomats from embassies of several predominantly Christian countries in Tehran.

Despite these concessions, however, the student leadership inside the embassy has maintained its resolution to try the hostages unless the deposed shah is returned to Iran to be punished for his alleged crimes. Following Khomeini's lead, they have labeled the embassy a "nest of spies" and lumped all 50 hostages in their charges of espionage.

The preoccupation with U.S. spying was demonstrated again today by announcement that an Iranian in the central city of Isfahan has been jailed on charges of providing information to the U.S. Central Intelligence Agency.

The alleged CIA source, identified as Jamshid Iranpour, was said to have been cleared by a local Islamic clergyman for work on the Isfahan revolutionary committee. Despite the mullah's certification, the state radio said, it was later discovered through documents found in the occupied embassy that Iranpour had served as a CIA contact.