MUNICH, FEB. 6 -- Chancellor Helmut Kohl, under pressure from the United States and other allies to pledge to modernize battlefield-range nuclear weapons, said today that the issue should be decided only when the western alliance develops a new "overall concept" for security strategy.

Kohl, speaking at the Wehrkunde conference, a high-level military affairs symposium here, did not spell out what such a comprehensive alliance policy should be.

He hinted, however, that West Germany would support modernization of battlefield, or tactical, nuclear arms -- those with ranges of less than 300 miles -- if the North Atlantic Treaty Organization agreed to begin early negotiations with the Soviet Union on reducing arsenals of such weapons.

That approach has been endorsed by some security experts in Kohl's Christian Democratic Union.

U.S. senators attending the conference said they were "disappointed" and "disturbed" by Kohl's remarks. They expressed concern that West Germany was backing away from a 1983 NATO decision -- known as the Montebello accord, after the Quebec resort where it was reached -- to deploy updated versions of tactical nuclear weapons.

The dispute within NATO, which pits West Germany against the rest of the alliance, is one of the most important strategy disagreements to arise in the wake of the signing of the Intermediate-range Nuclear Forces (INF) Treaty.

The United States believes that it is essential to modernize tactical nuclear arms in coming years to strengthen NATO's nuclear deterrent.

Such weapons are not affected by the INF pact, which only covers missiles with ranges of between 300 and 3,500 miles. The United States is particularly interested in seeing deployment of a new version of the Lance battlefield nuclear missile.

U.S. Secretary of Defense Frank C. Carlucci, in a speech prepared for delivery at the conference on Sunday, said modernization programs foreseen under the Montebello accord "continue to have high priority for NATO."

He said such modernization programs were "requirements that NATO has identified prior to and independent of the INF treaty, and none of them is constrained by the treaty."

The Bonn government is resisting modernizing tactical nuclear arms because such weapons would most likely be used in West Germany, which would be the principal battleground in case of a European war.

Under pointed questioning from American and British participants at the conference, Kohl repeatedly declined to commit West Germany to go through with modernization of tactical nuclear weapons.

"Let us come to grips with these questions in terms of an overall concept," Kohl said.

Such a strategy would fix NATO's approach for all types of arms control negotiations and for deployments of other kinds of new weapons, Kohl said. He did not provide details.

The Bonn government is reluctant to risk a domestic political row over modernization of tactical nuclear weapons without knowing in advance if it will be asked as well to support deployment of other new types of nuclear weapons, according to security experts in Kohl's Christian Democratic Union.

Kohl said repeatedly that he was under domestic political pressure over the issue. He even suggested that West Germany might alter its position after state elections in the spring.

"For domestic reasons, some things are put differently before elections than they are after elections," Kohl said.

The outgoing U.S. undersecretary of defense, Fred Ikle, said the United States "surely" would have "welcomed" a commitment here by Kohl to modernize tactical nuclear arms. But he said Kohl's position was understandable given his domestic political situation.

Kohl said West Germany would not accept elimination of all tactical nuclear arms, as the Soviet Union favors.