France today threatened to retaliate for future Libyan acts of terrorism against southern Europe, while confirming that it had refused to allow U.S. fighter planes on a bombing mission against Libya to fly over French territory.

An official statement issued by the Foreign Ministry disassociated France from last night's U.S. bombing raid, while stopping short of condemning the Reagan administration's action. It appeared to reflect the ambiguous attitude taken by many West European countries in deciding how to deal with the Libyan leader, Col. Muammar Qaddafi.

Although the French government refused to give any public explanation for why it refused the U.S. request for overflight rights, well-placed officials privately linked the decision to delicate negotiations for the release of French hostages in Lebanon. Attempts to secure the release of the eight captives, who are being held by pro-Iranian Moslem groups, could be jeopardized if France was seen to be helping the United States take military action against Libya, officials said.

A French government spokesman said that the decision to refuse overflight rights for the F111 bombers stationed in Britain was made jointly by Socialist President Francois Mitterrand and conservative Prime Minister Jacques Chirac at a meeting on Sunday morning.

The officials said Mitterrand and Chirac also discussed attempts to improve relations with Iran, which is widely assumed in France to hold the key to the fate of the eight hostages.

Diplomats here said that foreign ministers from the 12 European Community countries are likely to discuss the U.S. bombing raid in a meeting in Paris on Thursday. The meeting, requested by Greece, follows a similar session in The Hague last night, which ended with an appeal to both the United States and Libya to avoid confrontation.

Today's French statement deplored what it called "the intolerable escalation of terrorism" which, it said, had led to "a reprisal action which itself renews the chain of violence." It added that France believes that European states should decide on "an appropriate response" in case Qaddafi carries out an earlier threat to attack southern Europe.

Elaborating on the statement in private, French officials said that the phrase "appropriate response" could include a threat of military action against Libya, either by France alone or by several West European countries.

"The Americans have assumed their responsibility and we will assume our responsibility as well," noted one government official, who asked not to be named. He said the French government was sympathetic to the U.S. argument that it acted in self-defense, while at the same time sharing the view of other West European governments that more time could have been given to negotiations.

France is already involved in a military dispute of its own with Qaddafi over its former African colony of Chad. Earlier this year, French planes bombed a Libyan-built airfield in northern Chad to cut a military supply line to Libyan-backed rebels fighting the government of President Hissene Habre.

While France's new conservative government has been anxious to stress its willingness to coordinate antiterrorist action with other western countries, French officials have cautioned that this does not imply automatic support for all U.S. initiatives. Gen. Charles de Gaulle took France out of the integrated military command of the North Atlantic Treaty Organization in 1966 and there are no U.S. military bases on French territory.

Diplomatic analysts here noted that it was possible to reach widely differing conclusions about West European readiness to cooperate with the United States against terrorism, depending on the point of departure. Yesterday's declaration by European Community foreign ministers accusing Libya of responsibility for terrorist acts was a significant step forward in European political terms -- but still fell short of the kind of tough action urged by the United States.

Similarly, some U.S. officials complained of French foot-dragging in negotiations last week to crack down on Libyan diplomats stationed in East Germany following the April 5 bombing of a discotheque in West Berlin. Others are impressed by the fact that France did in the end consent to heightened security measures that will have the effect of restricting the movements of Libyan diplomats in the western sector of the city.

French officials said that a factor in the decision to turn down the U.S. request for overflight rights was the knowledge that it was not vital to the success of the bombing mission. According to Defense Secretary Caspar W. Weinberger, the French refusal meant that the American aircraft had to fly an extra 2,400 miles to skirt the western coast of Europe on their way to Libya.

The Libyan ambassador in Paris, Hameed Houdeiry, today congratulated France on turning down the U.S. request. Describing the French decision as "a responsible reaction," he also said Britain would have to assume "responsibility" for its "direct contribution" to the U.S. mission.