A huge demonstration in support of Jews wishing to emigrate from the Soviet Union booed a statement of support from President Reagan that was read to the crowd yesterday and demanded action instead of talk.

Tens of thousands of people, holding aloft poster portraits of "refuseniks," Jews who have requested and been refused emigration visas, gathered near the United Nations to show their solidarity with Jews in the Soviet Union.

The demonstration was attended by U.S. Ambassador to the U.N. Jeane J. Kirkpatrick, Mayor Edward Koch, New York's senators and entertainers such as actor Gregory Peck and singer Paul Simon.

"My administration remains committed to do everything possible to assist the emigration of Jews and others who wish to leave the Sovet Union," the president's message said, "and to bring before the eyes of the world the Soviet government's continued refusal to grant its citizens the basic human rights to which men and women everywhere justly aspire."

The statement was roundly booed and countered with chants of "We want action."

The focus of the 11th annual protest sponsored by the 85 organizations of the Greater New York Conference on Soviet Jewry was an apparent Soviet crackdown that has allowed the least number of Jews to leave the Soviet Union in a decade.