The Vatican yesterday broke with tradition and announced that it will admit dissident Episcopal priests, including those who are married, to the Roman Catholic priesthood in this country.

The new policy will create a sort of church within the Catholic church for those who left the Episcopal church when it allowed women to be ordained as priests and modernized its liturgy.

A spokesman for the Roman Catholic hierarchy stressed that "the initiative came from the Anglicans and not from us."

'We have to assume," he added, "that they [the dissident Anglicans] were spiritually and humanly in a difficult situation . . . that when they say they feel they belong now in the Roman Catholic Church we have to believe them."

The new directive marks the first time that the Catholic church in this country has prepared to welcome married men into its priesthood. Although an Eastern European branch of Catholicism known as the Byzantine Rite does ordain married men, Byzantine churches in this country are not allowed to ordain those who are married.

The dissident Episcopalians will not be received into the Catholic priesthood automatically but must be reordained on a case-by case basis, with each man evaluated by the Vatican's Sacred Congregation for the Doctrine of the Faith.

Those who are married may remain so, but they will not be eligible to become bishops and may not remarry if their wives die.

The Catholic church does not allow its own priests to marry, although it does allow widowers to become priests. In recent years, as the world wide shortage of Catholic priests has grown more acute, the church has felt increased pressure, particularly from third world countries, to change that restriction.

Archbishop John R. Quinn of San Francisco, president of the American Catholic heirarchy, would not speculate on the number who might be involved. "The announcement has just been made this morning," he said yesterday in a telephone interview. "We'll have to wait and see what the response is."

Several thousand Episcopalians -- their exact numbers are unknown -- split from the Episcopal church after it decided in 1976 to admit women priests and adopt a revised Book of Common Prayer. But the Anglican Church of North America, which the dissidents founded in 1977, has since splintered over a variety of issues. Of the group's five original dioceses, two have seceded and one is virtually inactive.

Perry Laukhuf, a layman from Amherst, Va., who has been a leader in the dissident movement, said he thought the Catholic offer would have few takers in his group. "The people in [my group] with very few exceptions, are people who want to remain Angelican," Laukhuff said.

The main appeal to the Vatican, according to Quinn, came from a California-based group called the Pro-Diocese of St. Augustine of CanterbuCanterbury, which Quinn said represented about 1,000 members and 63 priests.

Quinn emphasized that the new policy is "precedent-setting . . . it's the first time that I'm aware of, in dealing with churches and groups from the Western tradition" that the Roman Catholic Church has provided for a continuing "organizational structure and common identity" of the newcomers with the Roman church.

Quinn expressed the hope that this "new development" would not "impede Anglican-Roman Catholic ecumencial dialogue," which has made considerable progress in the last decade toward reuniting the two churches. The Anglican Church was founded in 1533 by Henry VIII when the Roman Catholic Church refused to allow him to divorce Catherine of Aragon to marry Ann Boleyn.

Episcopal leaders were skeptical about the new Vatican policy.

"There's no question but that it will have a damaging effect [on the discussions]" said Cynthia Wedel, a president of the World Council of Churches and an Episcopal lay leader and ecumenical pioneer.

Reached at a WCC Central Committee meeting in Geneva, Wedel said the decision by the Vatican was "kind of contrary to the really good relationships we have had" with the Catholic Church. "I really am amazed," she said.

Quinn said that there had been "some consultation" with Episcopal leaders in this country on the matter. However, a spokesman for Bishop John M. Allin, presiding bishop of the Episcopal Church, said he was informed of the Vatican's action by phone only the day before the public announcement was made.

Allin, who also is at the Geneva meeting, declined to comment on the issue. Shortly after the Episcopal Church approved ordaining women priests, Allin said he did not support that position, and he helped push through a conscience clause that made the ordination and deployment of women priests optional for bishops.

The Rev. William A. Wendt, a Washington pastor who worked hard for the ordination of women in the Episcopal Church, reacted grimly to the Vatican's action. "You don't play in other people's pastures," he said. "It's stealing other people's sheep."

Wendt speculated that yesterday's announcement might encourage more people to leave the Episcopal Church because "now they will have a place to go."

In setting the conditions for admitting Anglicans, the Vatican's sacred congregation emphasized that such a move "is properly understood as the reconciliation of individuals" with the Catholic Church, Quinn said. Anglicans will be required to make personal professions of faith in Catholicism, including accepting the authority of the pope and hierarchy.

Quinn guessed that the Anglicans might continue to use at least some portions of the 1928 edition of the Book of Common Prayer in their liturgy. This edition of the prayer book was one of the rallying points in their split from the church.

Quinn said the Catholic bishops would set up "some kind of a liaison of a bishop or a committee of bishops," probably at their November meeting, to implement the new arrangement.