A major interfaith observance of Martin Luther King Jr.'s birthday will be held Monday night in a Mormon church in the San Fernando Valley--a first for the ultraconservative, 8-million member denomination, which has been criticized in the past for its anti-black image and self-imposed isolation from mainstream religion.

No Mormon church has ever hosted an event commemorating the occasion of the civil rights leader's birth, church officials said. The service, to be held at the Mormons' Van Nuys Stake, or church center, will be the main interdenominational observance of King's birthday in the San Fernando Valley.

"Mormons have taken part in King celebrations before but we don't know of any service that has been conducted at one of our chapels," said Jack Adams of Chatsworth, a regional spokesman for the Church of Jesus Christ of Latter-day Saints, based in Salt Lake City, Utah.

The Mormons' hosting of the event reflects the church's attempt to "look for ways in the Judeo-Christian community that we can join efforts for the betterment of life and standards," Adams said.

Before accepting the offer by the Van Nuys Stake to host the King service, the sponsoring Valley Interfaith Council sought the advice of black leaders in the Valley.

"The Mormon Church really had some image problems a while back, but everyone told us it would be a good idea," said Barry Smedberg, executive director of the interfaith council.

"I told Barry that we need to break down the old feelings between blacks and the Latter-day Saints," said Bill Huling, a counseling psychologist at Cal State Northridge, who was one of the black leaders Smedberg consulted. "Black people used to dread the Mormon Church, but where the church stands today is a complete turnabout."

The Rev. William T. Broadus, pastor of the predominantly black Calvary Baptist Church in Pacoima, said that he did not object to meeting in a Mormon church. "Martin Luther King stood for the brotherhood of man. Mormons or anyone else who want to recognize what King did for our society are welcome at any ecumenical event," Broadus said.

In the 1970s, protesters accused the Mormon Church of fostering racial discrimination through its longtime policy of barring blacks from its priesthood. To most Mormons, those protests reinforced a sense of persecution they have felt throughout their 162-year history.