French President Valery Giscard d'Estaing left Saudi Arabia today, concluding an 11-day tour of the Middle East that has helped push Israel deeper than ever into isolation from Western Europe.

The French leader got big headlines all over the continent for his insistence, in much more specific terms than he has used previously, on the right of the Palestinian people in "self-determination" and of the Palestine Liberation Organization to participate in peace talks.

Despite official Israeli protests to France, the other eight members of the European Economic Community have been making clear their fundamental agreement with the French position. This includes even the Netherlands, the European government that has consistently been the friendliest toward Israel, even at the cost of a stringent Arab oil boycott in 1973.

Although officials are taking care not to say so publicly, the European position is based on the assumption that the U.S.-led Camp David effort is doomed to failure. American special ambassador Sol Linowitz is currently negotiating between Israel and Egypt to work out a mutually acceptable status for the Israeli-occupied West Bank and Gaza Strip.

Egyptian Foreign Minister Mustafa Khalil, who has been in Paris for medical treatment, is being widely quoted here by authoritative sources as telling French officials that he expects nothing to be accomplished by the May 26 deadline for the Camp David talks. Khalil reportedly has said the Cairo government will react strongly to the failure for public effect, but that it understands very well that nothing can be expected until after the U.S. presidential election on Nov. 4.

The clear implication is that the Egyptian government also understands that it is unrealistic to expect a U.S. government to put pressure on Israel during an election campaign.

The private view of French officials is that British Foreign Secretary Lord Carrington has become active in Middle East diplomacy because he understands the need to fill the void between the expected failure on May 26 and Nov. 4 with an appearance of diplomatic movement. Otherwise Egyptian President Anwar Sadat would be left exposed with no prospect of progress.

"We won't let ourselves be outflanked by the British. We'll stay out front," said a French official. One U.S. observer said, "The British and French are playing slapjack," a card game in which the players compete by matching cards of the same value. The object is apparently to show that each is at least as good a friend of the Arabs as the other.

The heads of the Middle East departments of the nine member states of the European Community are to meet Tuesday in Rome in preparation for a meeting there Thursday of the political directors of the nine foreign ministries "to meditate about the Middle East," as French officials put it.

It is assumed that this is an attempt to define a common position for the European summit scheduled for March 31.

The Israeli ambassador in Paris, Meir Rosenne, who is close to Israeli Prime Minister Menachem Begin, told a press conference today that "the nine cannot even agree on the things that directly concern them, so they are trying to reach an agreement on Israel's back.

The umbrella organization of the French Jewish community issued a bitter statement saying that "by taking the heavy responsibility of interfering in the talks on [West Bank] autonomy before their finishing date, the president of the republic is compromising the Israeli-Egyptian agreement and hindering the march toward peace in the Middle East."

During Giscard's tour, the president of the Jewish organization, Baron Alain de Rothschild, went to protest personally to Prime Minister Raymond Barre.

By contrast, Yasser Arafat, head of the PLO, today hailed Giscard's "courageous step" and said he hoped the next step would be French recognition of the PLO. He said he hoped to visit Paris soon.

While French officials say there is no question of starting any diplomatic initiative before May 26 because no one in Europe wants to be accused of torpedoing the Linowitz effort, that does not exclude a joint European statement before that date.

French officials nevertheless, say privately that they have no illusions that there can be any real progress until Begin is replaced as Israel's prime minister. The Begin government is generally unpopular to Western Europe.

Egypt's Khalil has indicated clearly that he does not consider the European approach to be particularly helpful, however. Speaking of Giscard, Khalil told the newspaper Le Monde last week, "Who will be authorized to speak for the Palestinians, according to [Giscard]? How can Israel be obliged to accept the Palestinian interlocutor that is designated? Unless there are satisfactory answers to those questions, we have no other alternative than to continue along the route that we outlined at Camp David. And we hope that others will not place obstacles in our path."

Washington Post London correspondent Leonard Downie Jr. reported that Britain is canvassing other countries about revising U.N. Resolution 242, the basic U.N. document on a general Middle East settlement.

The British are understood to be seeking consensus on the idea that the PLO should recognize Israeli's right to exist in exchange for Israel's recognition of the Palestinian right to claim nationhood.

The British are also apparently showing sensitivity to allegations of undercutting Camp David. Ian Gilmour, Lord Carrington's deputy and his spokesman in the House of Commons, said today: "The nine are talking amongst themselves and with others but there is no intention to cut across the Camp David process."

A U.S. source noted that there is no fundamental disagreement between the emerging West European position and the long-term implications of U.S. policy but that the timing of the European moves cannot help but be a disservice to the Camp David efforts. "The United States doesn't want to find itself isolated with Israel," he said. "But I guess we can live with it if we have to."

What seemed to give particular weight to Giscard's statements, he said, were the circumstances -- making them "during a solemn imperial procession down the Persian Gulf, and then in Jordan."

French officials stress that Giscard won a great victory for Israel by getting its neighbor, King Hussein of Jordan, to sign for the first time a communique recognizing "the right of all the states of the region to live in peace within secure, recognized and guaranteed frontiers." The communique applied that principle to Israel by implication only.

There was a great deal of criticism in France of the four previous communiques that France signed with the gulf emirates because they spoke of Palestinian self-determination without alluding to Israel's right to exist as well.