French communists hammered a deeper wedge between themselves and their ruling Socialist partners this month by supporting a Kremlin drive to include France's nuclear arsenal in the Geneva arms control talks.
Such a position could put pressure on American arms negotiators, who insist that both French and British missiles are independent of NATO.
In parting ways even further with President Francois Mitterrand, the communists hope to strengthen their identity and attract voters who have crossed over into the Socialist camp. Party leader Georges Marchais wants to reverse setbacks in recent local elections and boost the party's dwindling national popularity.
The party, which holds only 4 of 43 ministerial posts, has found itself more and more hamstrung in its efforts to define a policy independent of the Socialists. The two have clashed repeatedly on such issues as Poland, Afghanistan, and more recently the Socialist austerity policy.
Following a visit to Moscow and a meeting with Soviet leader Yuri Andropov, Mr. Marchais articulated his party's position - which had been taking shape since last May - to have France's missiles be counted alongside NATO missiles in talks to reduce intermediate-range nuclear missiles in Europe.
''We must begin on the path of a balanced reduction of arms, taking account of the entire amount that exists on either side, East and West,'' he repeated to party officials in a meeting last week.
The President's rebuff to Mr. Marchais's stated position was swift. ''Everything that concerns national independence and territorial integrity will be decided neither in Moscow, nor in Washington, nor in Geneva, but in Paris and by myself,'' he told a television interviewer recently.
With NATO's deployment of United States Pershing II missiles due to begin in December, the issue of whether French nuclear weapons should be included in the Geneva talks has assumed added importance.
Mr. Mitterrand maintains that France's nuclear deterrent is under an independent command for the defense of France, and as such has no place at the Geneva discussions. France is not a member of the military command of the North Atlantic Treaty Organization.
The Communist Party is said to be increasingly unhappy with Mr. Mitterrand's anti-Soviet line, and particularly with his signing of a declaration at the recent summit in Williamsburg that called the nature of Western security ''indivisible.''
To dispel Mr. Mitterrand's implication that the Communist Party leader was questioning France's independent nuclear capability, Mr. Marchais stated that ''in no case do we accept having called the independent national defense of France into question.''
The party has sought to cast itself as leader of the French pacifist movement. Last month the communists helped organize a disarmament rally. But some political observers think the communists may have done more harm than good to themselves with their recent statements. To maintain its credibility as a spokesman for European pacifism, the party must not appear to be a tool for Soviet interests.
For the moment, Mr. Marchais has stressed that his party wishes to remain in the government, and that differences on arms control will not serve as cause for a split.