France, Britain, Italy and the Netherlands today formally announced their willingness to participate in the Sinai peace force in a series of carefully linked declarations that reiterated European doubts about the Camp David peace accords.

The United States and Egypt immediately welcomed the European move, but Israel expressed reservations. And several Arab leaders warned that European participation in the peace force would jeopardize European-Arab relations.

In Canberra, Australian Prime Minister Malcolm Fraser announced Tuesday morning that Australia also would contribute troops to the Sinai force, The Associated Press reported. Fraser said in a brief statement that the European participation satisfied his government's requirement "for a balanced multinational force and makes it possible for Australia also to participate."

The European announcements, full of deliberate ambiguity, were the product of weeks of diplomatic give-and-take. They represent an attempt by the four nations to contribute to the U.S.-sponsored force under conditions that avoid a threatened Israeli veto and simultaneously remain faithful to European policy. That policy holds that the Camp David agreements are insufficient to produce a comprehensive Middle East peace.

[Washington Post correspondent William Claiborne reported from Jerusalem that the Israeli Foreign Ministry declared: "The statements made public until now seem in contradiction to the Camp David agreements." The Israeli Cabinet plans to consider the European declarations in a meeting Sunday, and high Foreign Ministry sources expressed doubt the declarations would be accepted, Claiborne added.]

Israeli Foreign Minister Yitzhak Shamir said Nov. 4 that "any statement indicating a contradiction" of the Camp David accords "will disqualify the party so declaring from participating in this force." He added, "Participating in the multinational force must be based solely on the agreement we signed -- we, Egypt and the United States -- in the framework of the Camp David accords. We will not accept anything that contradicts or deviates from these documents."

[In Damascus, Syria's minister of state for foreign affairs, Faruq Shar, handed the heads of the diplomatic missions for the four nations a message warning them against contributing to the peace-keeping force. After the four diplomats briefed Shar about their governments' intentions, he explained to them "the extent of harm their decision may do to Arab-European relations," according to a Foreign Ministry spokesman, Reuter news agency reported.]

[In Fez, Morocco, where Arab foreign ministers are preparing an Arab League summit meeting to begin Wednesday, Arab League Secretary General Chedli Klibi had warned the Europeans on Saturday that they would put economic, political and cultural ties with the Arab world at risk if they participated in the Sinai force, The Associated Press reported.]

The United States and Egypt regard European participation as a major breakthrough for the Sinai force. If it can be worked out with Israel under conditions acceptable to Europe it would broaden international support of the Egyptian-Israeli peace treaty in the nervous atmosphere created by president Anwar Sadat's assassination and Israeli worries over whether his successor, Hosni Mubarak, has the will and the power to continue Sadat's peace policies.

An appendix to the Camp David accords originally provided for a force under United Nations auspices, but this proved impossible because of Soviet and Arab opposition.

It now will be known as a multinational force and will be directed by the United States, which is contributing up to 1,200 troops to help patrol the Sinai after Israel's final withdrawal in April.

Units also have been promised by Colombia, Uruguay and Fiji. After European participation cleared the way for Australia to join, New Zealand was expected to take part as well. The force is to be 2,500-man strong.

But even if, as diplomats have indicated, the force would be limited to logistical and medical units, it would imply for the Arabs support for the Camp David process.

That process is regarded in the Arab world as an Egyptian sellout of the Arab and Palestinian causes and has been anathema there since its conclusion in September 1978.

The four Europeans made their announcement today in three delicately orchestrated statements to avoid angering Israel and the Arab states and to satisfy the 10 European Community members.

* The first statement, attributed to the European Community as a whole, blessed the French, British, Italian and Dutch decisions to participate in the force. Their move, it added, "responds to the willingness often repeated by the community's member countries to facilitate any progress toward a comprehensive peace accord in the Middle East based on mutual acceptance of the right of existence and security of all states in the region and the necessity for the Palestinian people fully to exercise its right to self-determination."

French diplomatic sources said the vague formula grew out of laborious negotiations seeking mainly to reconcile Israeli objections with Greek insistence that the statement include terms favorable to the Palestine Liberation Organization. The new Greek government recently recognized the PLO and announced plans to accord it diplomatic status.

The French sources also pointed out that the declaration carefully avoided recalling Europe's Middle East policy-declaration at Venice in June 1980, which Israel had explicitly warned would be unacceptable. The Venice declaration urges acceptance of the existence and security of all states in the region, "including Israel," and justice "for all peoples, which implies recognition of the Palestinian people's legitimate rights."

* A second statement, attributed to the four nations only, set out terms for their participation "only in order to maintain peace in the Sinai after Israeli withdrawal." It also underlined that their participation does not mean rejection of any future peace accords, apparently in a nod toward the Saudi peace plan now being discussed in Fez.

The second statement pointed out -- in clear reference to the Europeans' belief that the Camp David peace effort has run into a dead end -- that "participation by the four governments in the multinational force does not prejudice their well known policy on other aspects of the region's problems."

This allowed the French and British governments to allude to their insistence that participation by the Palestine Liberation Organization would help any peace negotiations, and that a Palestinian state probably will have to be born before lasting peace can be reached in the Middle East. At the same time, it would allow the Israeli government of Prime Minister Menachem Begin to say that these policies, strongly opposed by Jerusalem, were not part of the four-nation declaration explaining European participation in the peace force.

* But a series of third statements -- issued separately in Paris, London, Rome and The Hague and described as "national statements" -- specifically urged PLO "association" with peace talks and reiterated European policies enunciated at Venice.

It added, in an obvious effort to blunt Arab criticism, " the four nations consider their support of the accords related to implementation of the Egyptian-Israeli peace treaty as altogether distinct and independent of the rest of the Camp David process."

Most European governments have regarded the accords as a useful contribution inasmuch as they produced the Egyptian-Israeli peace treaty. But they also have judged the other part of Camp David -- the effort to satisfy Palestinian aspirations through limited autonomy in the West Bank and Gaza -- as an exercise doomed to failure.

French Foreign Minister Claude Cheysson recently expressed hope that, by contributing to the Sinai force, the Europeans can "make a bridge" between the stalled Camp David autonomy talks and broader peace negotiations perhaps based on the Saudi plan.

Washington Post staff writer Don Oberdorfer reported from Washington:

The State Department "warmly welcomed" the European decision in an official statement intended to make clear the U.S. hope that the European participation will be accepted by Israel. State Department sources said, however, that there is no guarantee that the Israeli reaction will be positive.

Israel was "not negative" when presented with the cautiously worded statement of the four European participants last weekend, the sources said. U.S. diplomats were very actively involved in discussing this statement with its British, French, Italians and Dutch authors, and reportedly felt that in its final form it would be acceptable to Israel.

There was more concern in Washington about the other two statements, that of the European Community and the "national statements" of the four participants.

A factor generating some optimism in the State Department was the belief that the American public considers the European willingness to participate in the Sinai force to be a breakthrough and would fail to understand a decision by Israel to reject it.