A national group of black political and civil rights leaders yesterday praised President Carter for refusing to end a U.S. economic boycott of Zimbabwe Rhodesia.

Carter's June 7th announcement that he would keep the boycott in place - for the moment, at least - "was in the national interest," the black leaders said.

The group, led by the Congressional Black Caucus and Transafrica, the Washington-based lobby on U.S. policy toward Africa, also said it supports an economic sanctions proposal that won unanimous approval last week in the House Foreign Affairs Committee.

Under the committee-approved measure, Carter would be required to lift sanctions by Oct. 15 unless be certifies to Congress that the sanctions should be maintained in the national interest.

"It's a compromise that leaves the matter to the president," said Randall Robinson, executive director of Transafrica.

However, Robinson and others at yesterday's news conference voiced strong disapproval of the Senate's vote last week calling for an immediate lifting of the sanctions, the most recent of which have been in place since 1977.

The black leaders, who also included officials of the NAACP and the National Urban League, said they would seek political retaliation against lawmakers who have been pushing for a quick end to the boycott.

"We want to make it clear that the black leadership is committed to respond to those in Congress who would embrace what is nothing more than a racist solution to the problems of Rhodesia," Robinson said.

The reference was to the April elections in what was then called Rhodesia. The voting, in which blacks were allowed to participate for the first time, produced a new, multiracial government in Salisbury under the leadership of Bishop Abel Muzorewa.