West German Chancellor Helmut Kohl said today that the Soviet Union's rigid stance was responsible for blocking progress at the Geneva negotiations to restrict medium-range nuclear weapons in Europe.

In a major speech to parliament, Kohl said the "small steps" taken at the arms talks by Moscow only underscored the "same immovable goals" of the Soviet leadership: to maintain its intermediate SS20 nuclear missiles and to prevent deployment of comparable weapons by the North Atlantic Treaty Organization.

Kohl, who will travel to Moscow on July 4 for a four-day state visit, said it was "absurd" to think the West lacks flexibility because it will not bow to the "maximal position" of the Soviet Union.

In Paris, NATO's Special Consultative Group reaffirmed the determination of the alliance to install intermediate-range missiles in Europe, absent progress toward an accord with the Soviets beforehand.

Kohl, reporting on the recent Williamsburg economic summit, criticized U.S. reluctance to alter economic policies that have engendered high interest rates and stunted a world recovery.

"It is unsatisfactory for us all that the United States is not yet ready to consider sufficient, practical steps to ease the monetary and financial situation of its partners," Kohl said. But the mild rebuke amounted to a retreat from earlier criticism.

At a Cabinet meeting last week after his return from Williamsburg, Kohl complained that it was "annoying and frustrating" that the United States had not curbed its huge budget deficits, which many people view as the chief cause of high interest rates.

In his speech today, Kohl also chided France, saying it blamed the United States for most of its own economic difficulties. French President Francois Mitterrand has charged that the U.S. interest rates have lured away from Europe badly needed investment money.

The chancellor cautioned that "those who stress the independence of European policies should not in the same breath place the main responsibility on the United States for interest rates, foreign exchange problems and the economic and political troubles of their own country."

Kohl's evenhanded approach, which he employed at the summit to mediate differences over arms control and economic issues, reflected his strong desire to alleviate friction within the alliance at a time when prospective stationing of new U.S. nuclear missiles in Europe could give rise to violent demonstrations and severe political tensions.

"If the Soviet leadership should make the mistake of overestimating the effect of its own propaganda and underestimating the steadfastness of the free western democracies, then it must be prepared for a bitter disappointment," Kohl said.

Kohl also urged the opposition Social Democrats to join in a consensus on security issues to demonstrate unity in the quest for "balanced and verifiable" arms control. Leading Social Democrats have expressed skepticism about U.S. intentions in the Geneva arms-control talks, especially after President Reagan said he believed the missiles must be deployed before the Soviets will negotiate.

The Social Democrats also have responded positively to the Soviet position that French and British nuclear-deterrent forces must be counted in any assessment of medium-range nuclear arsenals between East and West. But Kohl, backing the view shared by governments in Washington, Paris and London, said the French and British systems have no role to play in the Geneva negotiations.

Staff writer John M. Goshko added from Paris:

NATO's Special Consultative Group, charging that the Soviet Union "blocks the way to progress" on an agreement to reduce medium-range missiles, declared that "the decision taken by NATO on Dec. 12, 1979, stands," and deployment of U.S. missiles in Europe is to take place in December.

Richard Burt, U.S. assistant secretary of state for European Affairs, acting as spokesman for the group, said, "We will begin deploying at the end of this year, absent concrete negotiating results in the intermediate-range nuclear force negotiations in Geneva."

The Special Consultative Group was set up to keep America's NATO allies informed about the progress of the U.S.-Soviet talks in Geneva. It includes all NATO members except France, which has withdrawn from military participation in the alliance, and its statement today is to be accepted by NATO foreign ministers at a meeting here Friday.

That meeting is the last high-level NATO gathering before the first of 572 Pershing II and cruise missiles are scheduled to be put in place in Britain, West Germany and Italy.

Despite continuing opposition from advocates of nuclear disarmament, western officials here indicate that the atmosphere in Europe has changed sufficiently for most NATO governents to feel secure in moving ahead with deployment.