Hit by a sudden upsurge in international terrorism, France has dropped longstanding objections to coordinating antiterrorist measures with the United States and other leading western countries, government officials said today.

The change in the French position could pave the way for the inclusion of a reference to fighting terrorism in the final communique to be issued by the summit of seven leading industrialized nations in Tokyo next month, according to government officials. It also defuses a potential row between Socialist President Francois Mitterrand and the new right-wing government headed by conservative Prime Minister Jacques Chirac.

While Chirac long has favored closer cooperation between western countries in fighting terrorism, Mitterrand has blocked previous U.S. attempts to raise the subject at annual western economic summits. He has argued that the summits originally were designed for the informal discussion of economic issues rather than the coordination of political policy.

A government spokesman, Denis Baudouin, told journalists that Chirac and Mitterrand both agreed that the struggle against terrorism should be discussed in Tokyo. Both have announced their intention to travel to Tokyo for the summit May 4-6, a departure from the usual practice of France being represented by the head of state alone.

In addition to President Reagan, the summit will also be attended by the leaders of Japan, Italy, West Germany, Britain and Canada.

Underscoring Chirac's intention to play a prominent role in French foreign policy, an area of special responsibility for the president under the Fifth Republic's constitution, the prime minister's office announced today that he will visit the West African state of Ivory Coast next week and hold talks with West German Chancellor Helmut Kohl in Bonn on April 17.

Seeking to play down the reports of a change in the French position on terrorism, the Elysee presidential palace released a statement later saying that France had always been in favor of antiterrorist cooperation and was not opposed as a matter of principle to "joint declarations on topical matters."

According to government officials, the change in the president's approach occurred before the March 16 election, which resulted in a narrow victory for a right-wing coalition headed by Chirac.

It appeared to coincide with a sudden flare-up in terrorist acts involving France, including a spate of bomb attacks in Paris and the kidnaping of a French television crew in Beirut.

Political analysts noted that Mitterrand, whose term does not expire until 1988, has been eager to demonstrate that there is a consensus in France on key foreign policy issues. His own role as president could be undermined if his claims to speak on behalf of France were challenged by his longtime political opponents in the new government.

While U.S. officials welcomed the signs of a change in French thinking on terrorism, some diplomats said it was not clear yet what form future cooperation would take. Until now, cooperation has been limited to a vaguely worded agreement to take action against countries harboring airplane hijackers. The Reagan administration has been urging its summit partners to allow working groups to coordinate antiterrorist measures over a much wider area.

Tonight's statement insisted that France would continue to resist attempts to turn the annual economic summit into a western "political directorate." It added that French foreign policy could not be tied to the decisions of "other bodies," an apparent reference to the summit, on the pretext of "a struggle against terrorism."

Since the formation of the new government two weeks ago, Mitterrand and Chirac have had a series of meetings at which they have sought to reach a working understanding on the principal foreign policy issues. Subjects discussed have included the Tokyo summit, the withdrawal of a French observer force from Beirut and plans to devalue the French franc this weekend, according to officials.

An official in the prime minister's office said that Mitterrand and Chirac probably would have separate meetings with President Reagan in Tokyo but that the details were still being worked out. Since each country is limited to three representatives at the summit, Chirac will take the place of Finance Minister Edouard Balladur. The French delegation also will include Foreign Minister Jean-Bernard Raimond.