Much of the Arab world, including Egypt, cautioned today against U.S. or Israeli military reprisals against Libya for last week's terrorist raids against airports in Rome and Vienna, as Libya backed off further from its earlier hard-line rhetoric praising the attacks.

In the Libyan capital of Tripoli, Libya's secretary for foreign affairs, Ali Treiki, condemned the attacks and said, "Libya had nothing to do with it."

Treiki's comments were in contrast with those of the Libyan leader, Col. Muammar Qaddafi, who, while denying responsibility for the raids, said in a news conference on Wednesday that they were justified as revenge for the Israeli air raid on Palestine Liberation Organization headquarters in Tunisia on Oct. 1. He threatened "endless war" if Libya is attacked.

Yesterday, Treiki called the Rome and Vienna raids "deplorable blood outrages," and in a briefing for reporters today he described them as "regrettable accidents."

In another sign that Libya was attempting to moderate its stance, a planned demonstration around the embassy of Belgium, which represents U.S. interests in Libya, was canceled today, according to news service reports from Tripoli.

In Tunis, the general secretariat of the 22-member Arab League warned that ongoing "threats and troop movements" directed against Libya "can only have disastrous consequences."

Clearly taking Libya's side in the growing confrontation, the Arab unity organization said in a statement that it remains "firmly at the side of any Arab state threatened with aggression."

The United States and Israel have placed responsibility for the Dec. 27 Rome and Vienna attacks, in which 19 persons were killed, including five Americans, on the radical Palestinian terrorist organization headed by Sabri Banna, better known by his code name, Abu Nidal. Libya is accused of harboring and supporting the group.

Israeli officials already have claimed the right to take reprisals. The United States has not ruled out military options and is readying ships and planes for deployment to the region. Both Washington and Tel Aviv have called for international sanctions.

State Department officials said proposals for economic and diplomatic steps have been prepared for discussion at high levels within the administration next week, staff writer Don Oberdorfer reported. Among the steps reportedly under consideration are new restrictions on sale of spare parts for oil equipment and other export curbs.

Meanwhile, Libya has marshaled verbal backing from Moscow to add to promises of support in recent days from their usual allies in the region, Syria and Iran.

But the sentiments from the Soviets have not yet taken on the guise of warnings.

The official Soviet news agency Tass reported a Soviet Afro-Asian Solidarity Committee statement that the Soviet public feels "serious concern" about recent Israeli and U.S. actions toward Libya and expresses solidarity with Libyans "courageously upholding their national sovereignty."

Moscow has made similar low-level expressions of support for Libya before, protesting such incidents as a 1981 dogfight over the Gulf of Sidra in which U.S. Navy F14 fighters shot down two Libyan jets.

But the Soviets, Qaddafi's main arms suppliers, also have moved during the past two months to equip Libya with SA5 antiaircraft units that could prove vital in a confrontation with the United States or Israel.

Other Soviet media have accused the United States of planning for "open terrorism elevated to the rank of state terrorism" against Libya.

The Arab League stand at this point, however, comes as the organization has suffered serious divisions between the more moderate Arab members -- including, in this context, PLO Chairman Yasser Arafat -- and such radical states as Libya and Syria.

Since a summit in Casablanca, Morocco, attended by moderate league members in August threatened to split the league in two, Saudi Arabia and other advocates of Arab consensus have sought to heal the rift through a series of high-level meetings in hopes of holding a full-scale summit in Riyadh this year.

The Arab League statement today reflects what some western analysts regard as a predictable attempt to use the threat against one Arab nation as a means of achieving greater unity among them all.

But there also were signs in statements issued throughout the Arab world that while concerns are mounting about the danger of reprisals leading to wider war, sympathy with Qaddafi does not run deep.

Abu Nidal is allegedly responsible for killing many PLO officials close to Arafat. The PLO condemned Abu Nidal to death in the mid-1970s and accuses Syria and Libya of backing him. Several PLO officials have said in recent days that they believe the Rome and Vienna raids were intended to undermine the current peace process and possibly subject Arafat to Israeli reprisals.

Senior Egyptian officials, whose government is bitterly opposed to Qaddafi and who blamed him and Abu Nidal for the bloody hijacking of an Egyptair flight to Malta in November, have expressed some reservations about the possible impact of U.S. and Israeli retaliation.

Egyptian presidential adviser Osama Baz told reporters today after a meeting here with U.S. Assistant Secretary of State Chester Crocker that an attack on Libya could lead to a dangerous escalation of violence in the region.

"We are sure that the people in Washington are not trigger-happy or looking for any military involvement," Baz said.

In Kuwait, which has suffered from a series of terrorist attacks during the past three years, Acting Prime Minister Sabah Ahmed Sabah said today that he stressed to U.S. Ambassador Anthony Quainton "that we are against terror [and] against threats to any Arab state."