A Paris magazine reported today that Saudi Arabia called in French antiterrorist commandos to help overcome the insurgents who seized the Grand Mosque in Mecca in November.

Citing sources in the Middle East, Le Point magazine said today that five gendarmes from France's elite antiterrorist force secretly flew to Saudi Arabia and took charge of 3,000 demoralized Saudi Arabian paratroopers and national guardsmen. The French reorganized the assault plans and provided some new equipment and the Saudi forces eventaully forced out several hundred heavily armed, well-trained rebels in the mosque's catacombs, the magazine said.

A denial of French involvement was issued by the French Foreign Ministry, but an official pointed out that Saudi Arabia would be severely embarrassed by confirmation of the alleged appeal for non-Moslem help to defend Islam's most holy shrine. A French radio station, Europe No. 1, claimed that it has confirmed the story independently. Several well-informed Western sources refused to deny the basis of it.

Le Point said that Saudi Arabia, unable to handle the crisis alone, decided against asking for U.S. help. Although the United States is heavily involved in Saudi defense and security arrangements, Saudi officials apparently were dismayed by U.S. inaction in Iran and upset with the Carter administration for alerting the world press, in statements in Washington, of the trouble in Mecca.

Le Point said that the appeal for french help was made personally by Saudi Arabia's King Khalid to President Valery Giscard d'Estaing.

Detailed arrangements were handled by Saudi Arabia's Interior Minister Prince Nayef ibn Abdel-Aziz, who reportedly has a close working relationship with French intelligence chief Alexandre de Marenches.

In the magazine's account, the five Frenchmen flew to Saudi Arabia on Nov. 23 after Saudi assault forces had suffered severe casualties in their initial attempts to rush the heavily armed, well-trained rebels in the first three days of the mosque siege.

The French team used the following week to reorganize the Saudi units' tactics and obtain new equipment including special antiterrorist grenades and gas canisters. The revitalized Saudi units cleared out the rebels while their French advisers watched, Le Point said.

Shortly after, the Mecca operation, Le Point said, Saudi Arabia informed France that it intends to step up its French military purchases.