Secretary of State George P. Shultz and French Foreign Minister Claude Cheysson announced tonight that they had agreed on six specific projects for a Western alliance effort to develop a coordinated economic and trade policy toward the Soviet Union.

The subjects include several that, in one way or another, already are under study by various Western organizations. But the new agreement also calls, for the first time, for an expanded role for NATO in evaluating how economic relations affect Western security.

The announcement appeared to end a bitter dispute between Paris and Washington that erupted when President Reagan lifted sanctions on the Soviet gas pipeline following what he said was agreement with major U.S. allies on many of the measures described tonight.

U.S. officials said that both France and the United States were anxious to put that quarrel behind them and were now engaged "in an honest effort to bury the hatchet."

The details of the agreement were disclosed jointly by Shultz and Cheysson at an unusual impromptu press conference at the French Foreign Ministry.

Reporters were summoned to the ministry, where an official dinner had been held honoring Shultz. Officials apparently had become concerned that comments by Shultz and French officials during the day had given the impression that little or no progress had been made on resolving some of the major differences that had developed in recent months between Paris and Washington over the Soviet trade question.

Earlier in the day Shultz had held a press conference in which he appeared extremely cautious, perhaps because the matter of trade with the Eastern Bloc countries has been such an inflammatory and politically sensitive subject in both capitals.

Similarly, it had been hard to tell from public statements by French spokesmen during the day that any progress had been made, because those statements also tended to stress French independence of action.

Tonight, Cheysson reiterated that no matter what the studies ultimately show, countries always have a right to act and decide in their own national interests. But on matters where national security is clearly involved, he indicated, France would undoubtedly abide by the studies' conclusions.

Cheysson also appeared to be anxious to show that previous quarrels had been put aside, referring occasionally to Shultz as "my friend George" as Shultz outlined the six areas of study.

The newest area involves a NATO effort to help the alliance focus on the broad concept of strategic impact of trade with the East. NATO's role was foreshadowed last week at its ministerial conference in Brussels when a communique called attention to the importance of East-West trade for individual countries but added, "The allies agree that bilateral economic and trade relations with the Soviet Union and Eastern Europe must also be consistent with their broad security concerns, which include the avoidance of contributing to Soviet military strength."

Shultz and Cheysson both said that ultimately Japan would have to figure in these policies, because though it is outside the NATO alliance it benefits from the alliance and thus must share some responsibility for care in its trading policies.

The other five studies include:

* An attempt to strengthen and speed up the work of a NATO group known as CoCom (for Coordinating Committee), which deals with questions of trade with the East in strategic materials.

* An effort to look at other types of high technology, including such items as oil and gas equipment, which could relate to military use. This also will be done by CoCom.

* An effort by the Paris-based Organization for Economic Cooperation and Development (OECD) to monitor the flow of credit to the Soviets, an area already generally handled by that organization.

* A study of alternate energy supplies potentially available for Western Europe, Japan and the United States. This will also be undertaken by OECD, with some help from the Vienna-based International Energy Agency.

* An OECD study of the general question of subsidies and preferential treatment in trade.

The ministers are hoping to get some results in time for review at a series of Western economic and NATO summit meetings next spring.

The Franco-American feud apparently resolved here tonight erupted in full force in mid-November after President Reagan announced that he was lifting sanctions against companies involved in building the Soviet natural gas pipeline after what he said was "substantial agreement to a plan of action" on strategic aspects of East-West trade. Reagan had imposed those sanctions as a reaction to the imposition of martial law in Poland last year.

The French, who had rejected Reagan's sanctions as an act of interference with international trade and a violation of contracts previously' signed, immediately announced that they were "not a party" to the agreement.

U.S. officials claimed privately that the French had been a party to it. Whatever the truth, the French deeply resented the implication that they had made concessions in their attitude toward trade with Moscow to get the sanctions lifted.

When asked today at his earlier press conference about the status of that agreement supposedly reached in Washington in November, Shultz said, "The question of whether or who agreed to what is becoming irrelevant."