President Abol Hassan Bani-Sadr charged today that 96 Americans had landed in Iran to carry out sabotage and assassinations over the next two weeks with the help of Iranian sympathizers.

Bani-Sadr made the claim in an interview with the official Iranian radio shortly after the Iranian prosecutor general's office reported the arrest and imprisonment of two American men for alleged participation in last month's aborted hostage rescue attempt.

[In Washington, the State Department said it had no information about the two men, who were not named, and had no immediate comment on Bani-Sadr's remarks. A White House spokesman called the Iranian president's charge "ridiculous" and "just not so."]

[The Defense Department said the only U.S. forces in the area were about two dozen ships in a task force off Iranian waters.]

Bandi-Sadr told the state radio, "This morning I had a telephone call from the United States saying that 96 Americans had been brought into various places, and it is understood they will start sabotage operations within two weeks." He said the Americans wouls also carry out "assassinations in various cities."

The Iranian president said that as part of the alleged mission "two helicopters" laden with arms had landed in a mountainous region in central Iran. He said the American agents were accompanied by 19 Iranians, all longtime residents of the United States, and that arms were already being supplied to rebels in northwestern Iran.

Bani-Sadr did not say when the Americans allegedly landed and offered no proof to support his allegations, which came amid signs of his own declining authority in a power struggle with Moslem clerical rivals.

Bani-Sadr said he had ordered government security forces to neutralize the alleged plot. He added that if some incidents did occur, this should not be seen as a reflection on the armed forces.

Part of the purported American mission was to create suspicion among Iranians about the loyalty of the armed forces and stir further unrest in the country, Bani-Sadr said.

The prosecutor general's office said the two arrested Americans were being held in Tehran's Evin Prison but would not specify what the charges were or provide other details about them. Another American, frelance journalist Cynthia W. Dwyer of Buffalo, N.Y., was arrested 10 days ago and is being held at the prison on charges of being a CIA agent.

Iran's ruling Revolutionary Council announced earlier that the approximately 200 Americans in Iran "will be kept under surveillance until . . . it has been proved that they do not intend to conspire against Iran."

In other developments in Iran:

Ayatollah Sadegh Khalkhali, who displayed the bodies of eight Americans killed in last month's failed hostage rescue mission, resigned his post as head of an antinarcotics unit, the state-run radio reported. The reported resignation came after Khalkhali was criticized and stripped of his official positions for destroying a huge marble tomb containing the remains of the deposed shah's father. Khalkhali was quoted as saying that "secret hands" were at work against him.

The armed forces said an Iranian Air Force Phantom jet collided with a minibus while being moved to a runway at Bandar Abbas Air Base and that six guards on the bus were killed.

The official Pars News Agency said some of the equipment abandoned by U.S. commandos last month has been put on display in the northeastern city of Mashad next to a building where some of the American hostages now are being held.

The Spanish news agency EFE, meanwhile, quoted reliable sources as saying Spain might host an international meeting to seek a solution to the U.S.-Iranian crisis. The agency said Switzerland could be a site for exploratory talks.