A coalition of Boston-area union groups, religious organizations and student activists plan to join a national march on Washington this spring to protest United States involvement in third world nations, organizers of the march said this week.

The Boston coalition of the Mobilization for Justice and Peace in Central America and Southern Africa, a national group which plans to hold a rally April 25 in Washington D.C. to protest United States involvement in those areas, held its first organizational meeting last Thursday.

Organizers said the coalition represented the first time that religious and union leaders had joined together to protest American foreign policy.

"It is significant that the Mobilization for Justice and Peace involves religious leaders and labor organizers and not just peace activist groups," said Tony Palomba, a staff member of the Mobilization for Survival--a Cambridge group supporting the march.

At its first meeting the group discussed its reasons for protesting American foreign policy, Palomba said. "We are calling for the United States to quit doing business in Southern Africa--both governmentally and privately; we want to put pressure on South Africa to stop the war with Angola; we want the United States to send no more aid to UNITA; we want South Africa to drop its occupation of Namibia; and we want South Africa to stop pressuring and exerting economic influence on Zimbabwe," said Palomba.

Palomba said the group also called for an end to United States involvement in Central America.

The Reverend Bill Albert of the community Church of Boston, who spoke at the meeting Thursday, said he is involved with the Mobilization for Justice and Peace because "the Reagan Administration supports oppressive regimes."

Albers, who represents the religious community, viewed the joining of religious and labor groups as a positive change.

"I readily join with labor groups," he said, adding that he felt labor and religious groups have many things in common. "We both believe in justice for the people, for equal access to freedoms, and for a share in the profits of work," he said.

Two Harvard student groups have involved themselves with the Mobilization for Peace and justice.

Siddhartha Mitter '89, head of the Southern Africa Solidarity Committee (SASC), said the group plans to send members to join the Washington-bound Mobilization, and Mitchell A. Orenstein '89, a member of the Committee on Central America (COCA), said members of that group will participate as well.

Orenstein said also that a group made up of local students opposing United State intervention in Southern Africa and in Central America has held organizational meetings and plans to join the April rally.