President Francois Mitterrand declared today that France would rejoin a multinational consortium to develop a sophisticated fighter aircraft for the next decade as a symbol of his government's commitment to greater European cooperation in high technology projects.

The French move reverses a decision in August to abandon the Eurofighter program because of a fundamental conflict over what kind of plane to build. France wanted a light and cheap ground attack version, while other countries favored a heavy air combat model.

Mitterrand, speaking at a press conference here following two days of talks with West German Chancellor Helmut Kohl, said the two leaders also concurred on the need to launch construction of a new generation of Airbus passenger jets.

The French president said that he changed his mind about participation in the fighter program because he firmly supported the evolution of a European aerospace industry through common ventures linking neighbors and allies. "If we want to foster this cooperation we must show good will, so I said France is ready to take part in the joint plane project," Mitterrand said.

France and West Germany often have advocated closer collaboration in industrial and technological sectors to promote greater European political unity and a more dynamic economic partnership so the continent may compete more effectively in world markets with Japan and the United States.

But the most ambitious efforts in Paris and Bonn to expand cooperation have stalled because of clashes of national interests.

Earlier this week, France and West Germany joined 16 other European countries in approving a charter and several pilot projects for the Eureka high technology research program initiated by Paris in April. But critical issues, such as how the program will be managed and financed, remain unresolved.

Kohl and Mitterrand agreed today to seek to establish a Eureka secretariat in Strasbourg, although other participants want the bureau attached to the headquarters of the European Community in Brussels.

France's stake in returning to the Eurofighter program, Mitterrand stressed, would represent no more than the "symbolic value" of a 5 to 10 percent share. The other partners in the project include West Germany, Britain, Italy and Spain.

The French president said his country still would pursue the creation of a light and cheap fighter plane suited to French needs.

Paris and Bonn will lead a consortium that plans to build new Airbus passenger jets to challenge U.S. models from Boeing and McDonnell-Douglas. The European versions, to be ready for service in the late 1990s, will consist of a twin-engine TA9 for short journeys and the four-engine TA11 for longer hauls. Britain and Spain also are expected to participate in building the aircraft, each of which will require investments of up to $1 billion.