Lithuanian President Vytautas Landsbergis appealed to President Bush yesterday for strong public support of his republic's effort to gain independence from the Soviet Union. In return, he got a low-key restatement of longstanding U.S. policy that calls for self-determination for the Baltic states.

Landsbergis, following his first meeting with Bush, said his republic is being threatened by the Soviets with "economic catastrophe" since its March declaration of independence. He said he is seeking "some sort of political protection from the United States."

As Landsbergis met with Bush here, Secretrary of State James A. Baker III was meeting in Houston with Soviet Foreign Minister Eduard Shevardnadze at a session in which food and medical aid to the Soviets were on the agenda.

The friendlier U.S.-Soviet relationship, reflected in the new efforts to aid the Soviet Union in the midst of its economic crisis, has made the plight of the Baltics a low-key concern in the administration.

The Landsbergis session was granted only after several requests and was given only passing notice at the White House yesterday, with no public statements by Bush and only a brief picture-taking session and written statement afterwards.

Two weeks ago at the 35-nation European Conference in Paris, the foreign ministers of the three Baltic states, which include Latvia and Estonia, were barred entry as observers because of Soviet objections. The United States supported observer status for the three nations, but did not press the issue at the conference.

Yesterday, White House press secretary Marlin Fitzwater said Bush had told Landsbergis that he hopes the Soviet Union will work with the Baltic republics without resorting to violence or threats. Bush, Fitzwater said, "reaffirmed" the historic policy of the United States, which has never recognized the forcible incorporation of the Baltics into the Soviet Union.

Landsbergis said after the session he was confident that Bush would "take an active policy when we are in danger" but would not specify what that might involve. He said he is seeking "some very clear statements in response to Soviet pretensions that they have sovereign rights over Lithuania."

Landsbergis, comparing the plight of Lithuania with that of occupied Kuwait, said, "I do not want to wish upon Kuwait the same that we have experienced, 50 years of waiting for our independence."

Landsbergis repeated his argument that attempts by Soviet republics to break away from Moscow do not amount to a disintegration of the Soviet empire but are a positive form of decolonization. He predicted a "commonwealth" of former Soviet republics.

Before the session, Fitzwater acknowledged that "tension" exists in the Baltics situation, even though the Soviets suspended their economic boycott of Lithuania while independence talks continued.

The suspension of the boycott eased what had become a major issue in the United States last spring. But last week, Soviet President Mikhail Gorbachev issued a presidential order forbidding any of the country's republics from setting up its own militia and declaring void any legislation by the republics that "contradicts Soviet defense capability."

The decree came as the Baltic states held their first joint session in history asking Soviet troops to leave their territory, and protesting Moscow's efforts to block their moves toward independence. Officials of the three states also informed Moscow they would not follow Soviet economic policies.

Landsbergis met with State Department officials before his 30-minute session with Bush. Before he leaves Washington tonight, he is to meet with Vice President Quayle and members of Congress who have been supporters of Lithuania.