NICOSIA, Cyprus (AP) _ The religious leader of Iran on Wednesday condemned the execution of 16 Kuwaiti Shiite Moslems in Saudi Arabia and called for the holy city of Mecca to be liberated ''from the claws of oppression.''

''The Saudi agents beheaded 16 of the best children of Islam ... and added another black page to the thick volume of their black book,'' Ayatollah Mohammad Araki said in a statement read on Tehran radio, monitored in Cyprus.

Araki, 99, was appointed paramount religious leader, or marja' taqlid, by the country's top theologians after the June 3 death of Ayatollah Ruhollah Khomeini.

Khomeini, who died of a heart attack at age 86, was Iran's highest religious and political authority. Ayatollah Ali Khamenei, voted to succed him in the political role, is a middle-ranking cleric and lacks the authority needed to rule on religious matters.

The 16 Shiites were beheaded after they were convicted by Saudi authorities of planting bombs in Mecca that killed a Pakistani man and wounded 16 other pilgrims July 10.

After the death sentences were carried out, Saudi television screened taped interviews of the condemned men in which they confessed to setting the bombs and said two Iranians at the Iranian Embassy in Kuwait supplied them with explosives and training. Iran denied it.

Araki said it was up to the Moslem clerics ''not to remain silent,'' adding:

''It is up to them to raise their cry to inform the public, to support Islam and the religion of God and to salvage the two holy places from the claws of oppression and the government of the blasphemers.''

Iranian leaders have long demanded that Mecca and Medina, Islam's holiest cities, be wrested from the control of the Saudi royal family and put in charge of an international commission.

Following the executions, Iranian leaders repeatedly have called for revenge against Saudi Arabia.

On Wednesday, four masked men who said they represented Hezbollah, or Party of God, in Kuwait and Saudi Arabia held a news conference in Beirut and threatened to punish Saudi Arabia.

The executions brought to an end recent efforts to improve relations between Shiite Moslem Iran and Saudi Arabia, which follows the Sunni Moslem sect. The two sects have been antagonistic since a split in Islam in the 7th century.

Relations between Tehran and Riyadh previously reached their nadir in 1987 when more than 400 pilgrims, most of them Iranian, were killed in clashes with Saudi security forces in Mecca.