Western diplomats said here today that they expect any terrorist response by Libyan leader Muammar Qaddafi to the U.S. attacks on Libyan patrol boats and antiaircraft missile installations to be delayed for weeks or even months, possibly until Americans have relaxed their defenses.

The state-run radio today continued broadcasting statements by Qaddafi made earlier this year vowing to send "suicide squads" into action against the United States and American interests abroad if Libya were attacked. And yesterday in Damascus, Syria, Palestinian terrorist Abu Nidal reportedly declared that any target that could be identified with the United States would now be considered fair game for his forces.

Qaddafi's support for Abu Nidal before the attacks on the Rome and Vienna airports Dec. 27, which the United States has blamed on Abu Nidal, was a major factor in precipitating the current violent confrontation between Tripoli and Washington.

Yesterday, Syrian Vice President Abdel-Halim Khaddam, whose government also supports Abu Nidal, met with Qaddafi here to discuss "the latest developments regarding U.S. aggression," the official Libyan news agency reported.

Tripoli remained quiet today. A major demonstration is expected on Friday, the anniversary of the evacuation of the British military presence here in 1970.

But the official news media here continued to claim the military engagements of the last two days as Libyan victories. Despite strong U.S. denials, Libya maintains that it shot down three U.S. warplanes in the Gulf of Sidra. In one dispatch, Libya added that it allowed American helicopters to search for a downed pilot.

Diplomats here said that in addition to his connections with Abu Nidal, Syria and Iran, Qaddafi appears to have built a much wider-ranging international network of contacts aimed at carrying out what the West considers terrorism.

These sources said they could not say how effective the network might be, but that its existence and general aims are a matter of public record here.

One veteran envoy said a plan of action by Qaddafi and his allies may have been "settled" about 10 days ago before the U.S. attacks, at what he called a "terrorism convention" here attended by as many as 1,000 representatives from all over the world.

While diplomats did not rule out immediate Libyan action, they said it was more likely that Qaddafi would build up his rhetoric over the next few days.

"Then things will calm down," one diplomat predicted. "Then maybe two or three months from now you'll have a wave of attacks."

The Second General International Conference of the World Center for Combatting Imperialism, Zionism, Racism and Fascism convened in Tripoli on March 15.

In his opening speech to it, Qaddafi declared that "no one in the world at large can stop us from waging a collective struggle against the joint enemy," the United States. He suggested specifically that "communication routes in the vital regions of the world" would be appropriate targets.

According to a text of the speech published by the official Libyan news agency, Qaddafi noted the attendance of "blacks from North America, Canada, South America and Britain," as well as American Indian "factions." He welcomed representatives of "the Greens and other alternative movements" from Western Europe, "revolutionary movements from French colonies," Kurdish "factions" from Iraq and Moslem rebels from the Philippines.

Diplomats said representatives from Palestinian factions opposed to Yasser Arafat also were present, but that they could not be sure exactly who attended because the three large hotels that housed the conference were kept off limits to unauthorized visitors.

In his March 15 speech, Qaddafi eulogized a recently slain leader of the Colombian M-19 guerrilla movement and promised to join hands with "our brothers, friends and comrades Cuban President Fidel Castro and Nicaraguan President Daniel Ortega."

Qaddafi spoke frequently of mounting pressure being put on Libya by the U.S. maneuvers off its coast and appeared to have anticipated some direct U.S. military action. He frequently alluded to the U.S. invasion of Grenada as an example of what Washington might attempt here. The purpose of the conference was to defend against such action, Qaddafi said.

The "World Center," as he called the organization, was formed in 1981 and held its first international conference here that August, nine days after two Libyan jets were shot down by U.S. warplanes in Qaddafi's first confrontation with the Reagan administration over the Gulf of Sidra.

Since then, he said, the organization has created "an international fighting force" that would operate "regardless of boundaries and without discrimination." Qaddafi spoke of secret organizations linked to the conference "throughout the world" and ready to act.

While Qaddafi's threats often have exceeded actions, some European governments appear to have taken them seriously enough this time to warn him publicly against striking at them if he lashes out at the United States.