A growing number of Carter administration specialists on Iran -- including embassy officials in Tehran -- have concluded that the shah's departure from Iran is now inevitable and desirable and should be encouraged by the White House, U.S. officials reported yesterday.

While White House and State Department spokesmen continued to repeat that the administration's view on Iran remains unchanged, developments inside the country suggested that Washington's confidence in the shah's ability to control the year-long violent protest against his rule and to protect Amercians in Iran is rapidly dropping.

American dependents in Iran continued to be encouraged by the U.S. Embassy to leave the country for their own safety, and the embassy reportedly was considering ordering its "nonessential" diplomatic personnel to leave. U.S. Air Force planes airlifted 295 military dependents out of Iran and several hundred American civilians left on commercial flights yesterday.

There is increasing discussion at all levels of the administration that the shah's presence in Iran at the moment may be the chief obstacle to formation of a civilian government that could prevent collapse into anarchy or an overt coup d'etat and bloody repression by the military, officials acknowledge.

But sharp disagreement has surfaced over the timing and purpose of what the shah has suggested would be "vacation" abroad.

Already apparent divisions within the administration over Iran policy appear to have significantly deepended within the last few days as more U.S. officials here and in the field have become convinced that Washington should support a political solution that eases Shah Mohammad Reza Pahlavi from power.

A series of interagency meetings at the State Department yesterday involving working level and senior officials produced strong debate on possible moves open to the United States, officials reported. But no agreement was reached within the groups on a recommendation for a change in policy.

From Tehran, Washington Post special correspondent William Branigin reported that U.S. officials are making it increasingly clear in the Iranian capital that they have given up on the shah and have accepted the principle that the shah must go abroad if a new civilian government is to be formed.

U.S. Ambassador William H. Sullivan had previously been identified in news accounts as one of the strongest advocates within the administration of giving total support to the shah.

State Department spokesman Hodding Carter "categorically" denied yesterday that there had been any shift in the administration's policy on Iran. "We are not telling the shah he should go. If U.S. officials are saying that, it does not represent American policy," he said.

Another State Department working-level official said that the embassy had made no recommendation in its reporting to Washington that the administration should abandon the shah.

But a well placed U.S. source said that serious discussion has begun within 40- to 50-member task force headed by the State Department's number three official, Under Secretary David D. Newsom, over recommending that the White House accept that the shah is an impediment to the formation of a new civilian government and that he should leave Iran.

The Newsom group, which includes representatives from the Defense Department, the Central Intelligence Agency, the Treasury and other government departments that deal with Iran, met yesterday at 10 a.m. for a general discussion, participants reported.

Policy choices were discussed in more detail at meetings of the group's five subcommittee throughout the day, but no agreement could be reached within the key planning subcommittee on a recommendation on the shah's future, official sources said. The Newsom group is due to meet again Thursday.

Gaining strength within the administration appears to be the argument that the shah's physical presence in Iran is the major impediment to formation of a civilian government by Shahpour Bakhtiar, a longtime member of the opposition National Front who was asked by the shah on Friday to form a new civilian government.

Representatives from the State and Defense Departments appear to be the strongest advocates of this argument within the Newsom group. Other agencies are reportedly arguing that without the shah in the country to command the army, order cannot be restored.

The White House's major concern at this point appears to be ensuring some future role for the shah even if he should leave the country temporarily in order to facilitate Bakhtiar's task. President Carter and his national security adviser, Zbigniew Brzezinski, reportedly continue to believe that the shah's presence in a constitutional monarchy is still essential to Iran's future.

But from Tehran, correspondent Branigan reported that informed Western and Iranian sources said American officials have given the impression that they prefer running the risk of the shah's leaving the country, and not being able to return, to continuing the present upheaval under his now greatly diminished authority.

The only clear support for Bakhtiar's effort to bring a "true social democracy" to Iran seems to be coming from the U.S. government, diplomatic sources said in Tehran. "The Americans are solidly behind Bakhtiar, the British about 50-50 and the French somewhat less," one diplomat said.

Bakhtiar said in accepting the shah's mandate to form a government that the Iranian ruler would leave the country and a "regency council" would represent him in his absence. Effective control of the military would then pass to the civilian government, the prime minister-designate claimed.

More militant politicans in the National Front have insisted that the Bakhtiar proposals do not go far enough since they would leave a vestige of the shah's monarchy and permit his eventual return. The military also has reportedly opposed the Bakhtiar plan.

Hopes of diminishing U.S. support for the shah seemed to be reflected in remarks over the weekend by exiled religious leader Ayatollah Ruhollah Khomeini, who has been a harsh critic of the shah and the American role in Iran. Khomeini said in an interview with The Washington Post in Paris that he would wipe the slate clean with Washington after what he termed the shah's inevitable downfall.

State Department spokesman Carter attached no significance to the ayatollah's apparent olive branch, however, and said at the regular briefing yesterday that the United States still had no intention of establishing contact with the Iranian dissident.