The Bush administration, in its toughest and most explicit policy statement on the violent Soviet crackdown in the three Baltic states, said yesterday it is considering curtailing "the whole range of programs of cooperation with the Soviet Union" if Moscow's repression intensifies.

Assistant Secretary of State Raymond Seitz, in an attempt to signal how serious the United States considers the crackdown, said both substantive and symbolic steps are under consideration. Officials said Seitz's statement reflected growing apprehension, based on troop movements, that further Soviet military action in the Baltic states might be imminent, as well as an assessment that the future of President Mikhail Gorbachev and the course of Soviet politics and national policy are at an important turning point.

"We are outraged by the killing of unarmed civilians in Vilnius by Soviet military units on January 13," Seitz said in testimony to a special hearing of the Congressional Helsinki Commission. Regardless of the degree to which Gorbachev authorized the action or was in charge -- questions still unanswered -- "we hold the Soviet leadership responsible for the actions of the Soviet leadership," Seitz said.

Several lawmakers at the hearing called for a more vigorous U.S. response to the crisis in Lithuania and the two other Baltic states, Latvia and Estonia, and for the administration to go beyond verbal condemnation to specific action. Some of the lawmakers made strong personal attacks on Gorbachev, saying he had deceived the West or abandoned his reforms. Others, however, said they are not yet willing to give up their belief in the Soviet president and his policies.

Seitz gave no details of the specific U.S. programs for the Soviet Union that are under review because of the Baltic developments, but said they include "programs in the commercial and financial areas," which are those of greatest interest to Moscow at the present time. He also noted White House spokesman Marlin Fitzwater's statement Monday that next month's planned summit meeting of President Bush and Gorbachev in Moscow is "up in the air." Whether the summit will take place as scheduled is "now a matter of some doubt," Seitz added.

Two high-ranking officials from the democratically elected Baltic governments, Dainis Ivans, a vice president of Latvia, and Bronius Kuzmizkas, a vice president of Lithuania, are en route to Washington and will be accorded "a very high-level public meeting" by the administration as a symbol of concern about the developments, Seitz said.

Seitz said the United States is working closely with European countries in an effort to deliver a coordinated message about the importance of peacefully resolving the Baltics disputes, and the risks to Moscow of "unacceptable behavior."

Among these efforts, he said, are consultations with other Helsinki Act nations about using a procedure that would require the Soviet Union to respond officially to an inquiry on the subject. Such consultations to prepare an official "human dimensions" inquiry have been taking place in recent days, officials said.

Seitz said the administration is also considering sending a high-level delegation to the Baltic states, either on its own or as part of a Helsinki-related delegation. In the past, the Soviets have refused visas to several such delegations.

"It would be tragic if the difficult but very real progress toward democratization that has been achieved in the Soviet Union in the past few years were to be undone by an ill-considered return to the methods of the police state," Seitz declared. "We ask the Soviet authorities to undo what has been done" in the Baltic states, he said.