In an effort to pressure communist Czechoslavkia into settling longstanding claims by U.S. citizens, the Senate Finance Committee yesterday approved a bill that would allow the United States to seize and sell several tons of Czech gold being held in this country.

The committee action is the latest move in an international legal battle that goes back to the end of World War II and that has periodically managed to inflame tempers in both countries.

The bill, introduced by Sen. Daniel P. Moynihan (D-N.Y.) is also being seen by both congressional and State Department officials as a move to strengthen the hand of U.S. negotiators who will travel to Prague on May 19 in one more effort to negotiate a solution.

In the aftermath of World War II, allied forces captured several tons of gold that had been stolen by the Nazis from several countries, including Czechoslovakia. The gold was turned over to a trilateral allied commission, composed of U.S. British and French officials, that was set up to handle eventual return of the gold.

About six of 24 tons of Czech gold were returned. But in 1948, after the communists took over, President Truman stopped further shipments pending settlement by the Prague government of claims by U.S. citizens and companies whose property had been nationalized.

Similar claims situations developed in other East European countries, and the United States negotiated settlements with Hungary, Romania and Poland. But the Czech settlement has never been completed. The two countries had reached agreement in 1974 but Congress rejected the deal as unfair.

According to the U.S. Foreign Claims Settlement Commission, the claims by the United States amount to about $105 million, including interest. There are said to be some 2,100 U.S. claimants, including individuals and corporations. About 8.2 tons of the gold is held in the Federal Reserve Bank in New York; an additional 10 tons is stored in the Bank of England.

The U.S.-held gold is worth about $127 million, according to yesterday's prices. Under Moynihan's bill, as congressional aides explained it, the United States would seize the gold here and offer it for sale to the Czech government at prevailing rates. If the Czechs rejec that, the gold would be sold, the proceeds invested and the interest used to pay the claimants. When everybody is paid off, the balance of the fund reportedly would be returned to the Prague government.

The Prague leadership is among the most rigid and hard-line in the seven-nation, Soviet-led Warsaw Pact; Washington's relations with the Czechoslavkian government have been sour and stagnant for years.