Despite British and French interpretations to the contrary, Israel says it has received in "plain language" from President Reagan that the United States remains unalterably opposed to a European Middle East Initiative outside the Camp David peace accords.

Israel's Foreign Ministry director general, Daivd Kimche, said today in an interview that the British foreign secretary, Lord Carrington, and French Foreign Minister Jean Francois-Poncet, in their recent meetings with Reagan administration officials, appear to have read into U.S. statements what they wanted to hear.

"We were told in very, very plain language by the presidnet and other officials that the United States does not see any alternative to the Camp David aggreements. They hope the agreements can be expanded, deepened and added to, but the European initiative is not conducive to the continuation of Camp David. This we were told in the plainest of language," Kimche said.

He said Foreign Minister/Yitzhak Shimir received such assurances from Reagan and Secretary of State Alexander Haig during his recent visit to Washington and that the assurances have been repeated through other diplomatic channels.

[The White House, queried about Kimche's declaration, declined comment. The State Department also declined direct comment, but a spokesman pointed out that U.S. policy remains commited to the Camp David process and is under review by the new administration.]

Since visits to Washington by Lord Carrington, British Prime Minister Margaret Thatcher and Francois-Poncet, reports from London and Paris have indicated a shift in the Reagan administration position to the point where U.S. hostility toward an independent European initiative in the Middle East -- strong under the Carter administration -- has diminished. tReagan also was reported to have indicated that the United States intends to move slowly on Camp David, therby giving the Common Market countrues an opening to pursue their own peace plan at least until Israeli elections, which are scheduled for next June 30.

Israeli fears of such a move were fueled by disclosure of a secret Common Market working paper that raises a number of options comprimising a call for Israel to withdraw from all Arab territory occupied during the 1967 war and since, including East Jerusalem, to make room for Palestinian self-determination. Israeli officials also have been concerened by intensified European pressure on the United States to approve such an initiative.

But Kimche said Reagan and Haig's assurances alleviated most of these fears.

"We've been concerned by this onslaught by the Europeans on the United States. We feared that it might affect opinion in Washington, but we are happy that it did not. We are 50 percent of the Arab-Israeli conflict. The European initiative is a nonstarter and we reject it totally and finally," Kimche said.

Kimche dismissed a suggestion that momentum has been building up in the European effort and that the lack of U.S. diplomatic initiative in the Middle East has encouraged Common Market countries to become more forceful in their efforts to supplant or at least complement Camp David.

So far, the Reagan administration's main pronouncements on the Middle East have been observations that regional disputes, such as the Arab-Israeli conflict, demand less urgent attention than the broader East-West confrontation. Moreover, the Reagan administration has indicated that it is not interested in resuming the stalled negotiations on West Bank and Gaza autonomy until after the Israeli general elections.

"Three months of marking time isn't so much. As the United States gets more involved in the Middle East again, which it will there will be less room for the European initiative," Kimche said.

Reagan, Kimche noted, is primarily interested in preventing any expansion of Soviet influence in the Middle East. Since the European initiative could bring the Soviets into the peace process, he added, it is unlikely to curry favor with Reagan. Moreover, he said, British and French suggestions of dealing with the Palestine Liberation Organization, which has close ties to the Soviet Union, would probably discourage Reagan interest in the European initiative.

The Common Market working paper does not specifically mention the PLO, but prescribes conditions that could result in a PLO-led Palestinian state.

Kimche conceded that the European effort to work outside the Camp David framework will probably intensify in July, when Britain takes charge of diplomacy for the European Community. But he said Israel will remain unmoved.

"The Europeans can shout from morning to night that we have to withdraw, and if we don't withdraw, their shouting won't make any difference, will it?" Kimche said.

He noted that Britian and France are the most aggressive advocates of the European initiative, and that it was not surprising to him that a "senior French Foreign Minisrty source," in a briefing yesterday with Paris-based Israeli journalists, said that France would not contribute troops to a proposed Sinai peacekeeping force because that would suggest French support for Camp David.

The Senior French source was Francois-Poncet himslef, Israeli journalists said.

Kimche said Francois-Poncet's comments parallel the Common Market working paper, which calls for total Israeli withdrawl to the pre-1967 borders, dismatling of Israeli settlements in the occupied areas, creation of a Palestinian entity to be administered by a transitional authority until Palestinians vote on their own future and Western military guarantees for secure borders.

Kimche stressed that while the paper reflects the views of France and Britian, many European nations are "less enamoured" with that view and are not ready to support an independent peace effort. He said that conclusion was "an impression drawn from conversations" with European officials.

Among the nations cooler to the initiative, he said, are West Germany, Denmark and the Netherlands. Kimche said in the months ahead, Israel will continue its diplomatic effort to curtail the Euroopean initiative.