A newspaper supporting President Abol Hassan Bani-Sadr today accused his major political rights of plotting to overthrow him. The charge publicly exposed an intense power struggle between the fundamentalist Moslem clergy and Bani-Sadr's secular supporters.

The newspaper, Islamic Revolution, which Bani-Sadr formerly edited and now is run by his close associates, said evidence of the alleged plot was contained in a tape recording of a political meeting of the hard-line clerical Islamic Republican Party. The paper printed a purported transcript of the tape in which the number two man in the party, Hassan Ayat, is quoted as talking about sharply reducing Bani-Sadr's power.

The newspaper said the discussion concerned "plots which were afoot to topple the people's president and capture power."

While the alleged tape recording does not mention a coup d'etat against Bani-sadr, Ayat is quoted as saying that reducing his power "will mean hammering him and hammering him hard." At another Ayat is quoted as saying, "A strong rush will begin, but it will happen to such an extent that Bani-Sadr will be completely crippled."

Later Ayat is reported to have said, "We shall have a plan, and even Bani-Sadr's father cannot do anything about it. Arrangements have been made such that, unlike the last time, he cannot put up any resistance."

This apparently referred to a fundamentalist call in April for a "cultural revolution" and a purge of the country's universities. Bani-Sadr managed to head off a crisis resulting from subsequent campus volence, and the universities were ordered closed early June 4.

In its commentary on the tape, Islamic Revolution said that if the plan succeeded "in topping the president by creating some riot," the country would become so fractured that no political group could control the situation. Iran already is beset by internal revolt in Kurdistan and sporadic violence in other provinces seeking autonomy.

"Therefore, such conspiracies threaten not only the president, but also the Islamic republican order," the newspaper said.

No date was mentioned for BandiSadr's overthrow. But the newspaper indicated it was to happen after June 4.

This was the first time Bani-Sadr has come out swinging after a series of attacks on his power by Ayatollah Mohammad Beheshti's Islamic Republican Party, which controls a majority in the newly elected parliament.

Moreover, there have been indications in recent days that Bani-Sadr has gained the public support of Iran's ultimate political and religious leader, 80-year-old Ayatollah Ruhollah Khomeini, who spoke out last week about divisiveness in the country.

Khomeini said then, in what some observers considered a hint to the Islamic Republican Party to stop working against Bani-Sadr, that internal bickering would do more harm to Iran's Islamic revolution than plots from outside.

Later, his son, Hojatoleslam Ahmad Khomeini, attacked as "traitors" to Islam a gang of stone-throwing Moslem fundamentalists who tried to break up a rally of a left-wing Islamic political group.

The article in Islamic Revolution said the purported tape of Ayat speaking at a party meeting was taken to Khomeini, "who became very upset after hearing it."

A spokesman for Bani-Sadr said the president has been indirectly referring to the contents of the tape in speeches over the past three weeks.

But until today, Bani-Sadr's comments on the Islamic Repulican Party -- which has frustrated his efforts to resolve the hostage crisis, name a prime minister and appoint high government officials -- have been low-key and philosophical.

The strongest attacks on the party have come from Foreign Minister Sadegh Ghotbzadeh, who Monday called the party's newspaper, Islamic Republic, "one of the most corrupt newspapers in Iranian press history."

In the purported tape, Ayat continually belittled Bank-Sadr.

"The President can merely give and take medals, welcome ambassadors and nothing more," Ayat is quoted as saying. "Bani-Sadr is trying, but he has no power. He cannot do anything for we have kept the iman [Khomeini], the constitution and the [Revolutionary] Council against him. The more he lets out a human cry, the weaker he will get by the day. People's opposition will grow until he is removed by them."