A new call by Soviet President Leonid Brezhnev for U.S.-Soviet negotiations "without delay" on nuclear force levels in Europe leaves open the possibility that the Russians will go ahead with such talks even if NATO decides next month to approve deployment of new U.S. medium-range missiles in Western Europe, U.S. officials said yesterday.

Previous statements by the Soviet leader in a major propaganda campaign against deployment of the new missiles had been less clear on this point, the officials noted.

Yesterday's editions of Pravda, the Communist Party newspaper, contained a new Brezhnev statement on the subject in the form of answers to questions.

Brezhnev said, "There will be a greater chance of positive results" in arms negotiations "if no decisions are taken on the production and deployment in Western Europe" of U.S. Pershing II and ground-launched cruise missiles.

By saying only there would be less chance of success in arms talks in the wake of a NATO agreement to deploy the new missiles -- Brezhnev seemed to be "slightly softening" his earlier statements, in the opinion of one administration analyst.

Another, however, said the consequences of the NATO decision were still 'vague" and that Brezhnev had "never flatly turned down" the idea of talks even though he sharply criticized the new U.S. missiles in his earlier statements.

U.S. officials looked upon the Brezhnev statement as an attempt to keep up the pressure on NATO governments who still might be persuaded to vote against the deployment proposal.

One said the Pravda statements was written because the Soviets "had been hoping for an answer" to brezhnev's earlier proposal and had not gotten it.

The United States and its NATO allies have decided to delay any response until after the deployment decision is made next month.

At that time, the alliance is also expected to unveil its own plan to limit European theater nuclear weapons.

Up to now, the Soviets have maintained that future negotiations aimed at limiting European nuclear forces would take place between the two superpowers in the context of SALT III.

At a press conference in Brussels last week, Valentin M. Falin, chief spokesman on international affairs for the Communist Party Central Committee, said the negotiations "must begin as quickly as possible after ratification of SALT II" and "must be conducted within SALT III because Russian and U.S. weapons are involved."

Falin repeated earlier assurances from Soviet leaders that other European nations "will take part in the negotiations" but said the form and identity of those countries would have to be worked out with the United States.