France and Britain, stressing the independence of their nuclear forces, yesterday rebuffed Soviet leader Yuri Andropov's proposal to cut Soviet nuclear missiles in Europe to a level deployed by those two countries.

Andropov's initiative, presented in a speech yesterday marking the 60th anniversary of the Soviet Union, was widely interpreted as a shrewd attempt to undermine the U.S. strategic commitment to Europe by equating Moscow's intermediate-range missiles with the French and British nuclear systems.

French Foreign Minister Claude Cheysson said he was "shocked" by the Soviet attempt to include the French nuclear arsenal in the "Geneva calculations" -- a reference to U.S.-Soviet negotiations to reduce their nuclear missile forces.

Cheysson stressed that the French nuclear force could not be introduced into the U.S.-Soviet arms-control talks because "we are independent."

"Does Mr. Andropov wish France to be integrated into the Atlantic Alliance so that our missiles would come under American command?" he asked.

In London, Prime Minister Margaret Thatcher told Parliament that Andropov's new initiative "would in effect leave the U.S. with zero intermediate-range missiles in Europe while the Soviets would have a considerable number left."

"We require not the peace of Poland, Afghanistan and Stalin but the peace of freedom and justice," she said.

In Bonn yesterday, government spokesman Juergen Sudhoff said that Andropov's proposals would be examined "with great care and with great seriousness." He added, however, that if Moscow sought to maintain a monopoly on strategic arms in Europe, such an initiative would be "politically unacceptable."

The cautious response by the West German government toward Andropov's speech reflected some anxiety that Moscow might be launching its long-anticipated "peace offensive" designed to exploit antinuclear sentiment in Western Europe.

Britain maintains 64 Polaris nuclear missiles on four submarines while France deploys 80 missiles on five submarines, as well as 18 land-based nuclear missiles.

In addition, Britain possesses 56 Vulcan bombers and France deploys 33 Mirage jets that can strike Soviet territory with nuclear weapons.

Both countries insist that their nuclear arsenals serve as independent strategic deterrents that must not be considered in the same category as Soviet SS20 missiles.

Washington contends that any effort by the United States and the Soviet Union to negotiate over the nuclear systems of third countries would greatly complicate their bilateral negotiations.

In the past, Moscow has conceded that Britain and France need not participate in the Geneva negotiations but it continues to insist that their forces must be counted in any final agreement to determine the European nuclear balance.

The deployment of the Pershing and cruise missiles in the absence of an arms-control agreement is designed to redress the advantage in intermediate nuclear weaponry that the Soviets achieved through the 333 SS20 missiles they have installed since 1977.

NATO's missile modernization plans also assumed symbolic importance by reaffirming U.S. intentions to defend Western Europe with nuclear arms in the face of Soviet superiority in conventional weapons.

By equating Soviet medium-range nuclear arsenal with the British and French systems, Andropov seemed to be attempting to undermine both elements of Washington's strategy.

Cheysson said that France's nuclear strategy, which is backed by the Socialist government as vigorously as its predecessors, was based on a "minimum size."

"If we diminish this nuclear arsenal, it will have no dissuasive value," he said.

Cheysson strongly defended the NATO "twin-track" strategy to deploy the new Pershing II and cruise missiles in West Germany, Britain, Belgium, Italy and the Netherlands beginning next December if the Geneva negotiations fail to make progress.

"Balance is the key to peace," said Cheysson. "The way proposed by Mr. Andropov is to introduce a completely different attitude to the arms game. This will not do. The only way is to base Pershings in West Germany, Italy and elsewhere."

He said that "for some years, the Soviet Union has accumulated terrifyingly fast and accurate nuclear weapons" aimed at Western Europe and that NATO's deployment of the modern nuclear missiles "might be necessary to redress the balance."

Cheysson insisted that equilibrium was crucial for peace and said he supported President Reagan's so-called "zero option" that calls on the Soviets to dismantle more than 600 intermediate land-based missiles if the United States cancels deployment of the Pershing and cruise missiles.

In his speech yesterday, Andropov called the zero option a "mockery" that, in effect, demands unilateral Soviet disarmament.

Some West Europeans, notably former West German chancellor Helmut Schmidt, have suggested lately that the zero option may be unrealistic and that a more flexible approach by the United States may be required for the negotiations to succeed