A renewed haredi boycott of El Al appeared imminent Sunday night after the national carrier flew a group of secular Israeli travelers from London to Israel, thus violating an agreement not to fly on Shabbat. The Council of Rabbis for the Holiness of the Shabbat, a haredi group, met Sunday to determine what steps would be taken against El Al. Rabbi Ya'acov Aryeh Alter, the Gerrer rebbe, announced that anyone planning to fly with El Al should cancel their flights if they could. The contested flight, which arrived here at 7:10 p.m., about two hours after the beginning of the shabbat, carried passengers travelling from Toronto to Israel, who were stranded in London due to a mechanical failure discovered en route. El Al provided religious travelers with a hotel in London for Shabbat. However, secular travelers were flown to Ben-Gurion. Technically, San Dor, an El Al subsidiary, operated the flight from London to Israel. But the same plane with the El Al insignia was used. The agreement signed between El Al and the haredim stipulates that any case in which Shabbat may be legally desecrated be approved by Chief Sephardi Rabbi Shlomo Amar. The haredim notified El Al in the agreement that in case of an unauthorized Shabbat desecration, passengers would cancel all future flights. An El Al source said in response that a freak series of mishaps caused the incident. "El Al CEO Ramano is on vacation in the Swiss Alps," said the source, "and was therefore out of the picture. Also, we had difficulty getting in touch with Rabbi Amar, who is supposed to decide how to proceed in these situations." According to the source, while secular passengers made their way to to Ben-Gurion, attempts were made to locate Amar. When contact was finally made, the plane was flying over Cyprus, and the rabbi ordered it to land. But due to technical difficulties, said the source, it was impossible to do so. "Rabbi Amar is the final arbiter between El Al and the haredim," said the source. "Whatever he decides, we will do... We are still obligated to respect and honor the needs of our religious customers."