US intervention creates problems for its allies. Italy's refusal to stop escape of PLO figure has marred relations with US

As the Achille Lauro sailed home to Naples, troubled waters were ahead for Italy's five-party coalition government under Socialist Premier Bettino Craxi. The Italians face the ire of the United States, which made an extradition request for the four alleged hijackers and especially for Palestinian guerrilla leader, Muhammad Abbas.

The Italian government apparently ignored the request and allowed Mr. Abbas (also known as Abul Abbas) to board a plane for Belgrade Saturday night, saying that ``there were no judicial grounds on which to hold him in Italy.'' The US government believes that Abbas, who leads a faction of the Palestine Liberation Front, masterminded this hijacking as well as previous terrorist attacks.

But observers here say that it would have been difficult for Mr. Craxi to hand over to the US someone representing a group with which he had been negotiating.

In a press conference on Thursday night Craxi claimed to know personally at least one of the PLO officials on board the cruise ship. A spokesman for the PLO delegation in Rome on Monday described their relations with the Italian government as ``extremely good.''

Domestic political criticism of Craxi's policy has come principally from his own defense minister, Giovanni Spadolini, whose miniscule Republican party is part of the government coalition.

The centrist pro-American policy of the Republicans is not in favor of the government's recent friendliness toward the Yasser Arafat and the PLO.

``I don't think that openings to the PLO can be justified or conceived as a means to diminish the risk of terrorism,'' said Mr. Spadolini in an interview with the leftist weekly L'Espresso. Spadolini, the secretary of the Republican party, met with party leaders Monday to decide whether to continue Republican participation in the government.

``It would be bizarre if we didn't continue to search for a solution to the Palestinian torment,'' said Foreign Minister Giulio Andreotti in a magazine interview.

Italy's task and aspirations as Middle East mediator may be harder now, says Valdo Spini, a Socialist foreign-affairs expert.

``What they perhaps don't realize in the US is our position in the Mediterranean and Middle East,'' he says, referring to Italy's multiple relations in that strife-torn part of the world.

Italy has had friendly ties with Egypt. And it wants to keep good contacts with Tunis, where the main PLO headquarters was situated before it was bombed by the Israelis on Sept. 25.

The Italian government heavily criticized Israel for the attack. But the flight of Abbas to Yugoslavia has opened Italy up to charges of having helped the escape of a Palestinian terrorist leader, which is likely further to complicate relations with Israel.