ST. LOUIS (AP) — The St. Louis Archdiocese has warned two Roman Catholic women that they will be excommunicated if they are ordained as priests on Sunday.

Rose Marie Dunn Hudson, 67, and Elsie Hainz McGrath, 69, are set to be ordained by a former nun as part of the Roman Catholic Womenpriests movement that began in 2002.

Only men are ordained as priests and deacons in the Catholic Church. The Womenpriests and the advocacy group, the Women's Ordination Conference, are among Catholics pressing to change that tradition.

Both women said they will ignore Archbishop Raymond Burke's warning.

''It's a typically hierarchical form of intimidation, and we will not be intimidated,'' McGrath said.

The archdiocese declined to comment about the letters, delivered by courier to the women's homes Monday evening. In them, Burke warned the women they would be committing a ''grave error'' and ''act of schism'' by trying to receive priestly ordination.

He reminded them that the pope has stated infallibly that only men can receive a valid ordination, and wrote that ''in order to protect the faithful from grave spiritual deception'' if they go forward, they would ''incur automatically ... the censure of excommunication.''

Further, Burke wrote, ''additional disciplinary measures will also have to be imposed.''

''What is he going to do, burn us at the stake, or what?'' Hudson asked. ''We're going to just totally ignore it. This is not unexpected. We wondered why it took so long.''

Both women have graduate degrees in religious studies and have been active in ministry for years.

Hudson is a retired teacher who has done prison ministry for the past 15 years. McGrath is the widow of a Roman Catholic deacon and has worked for the archdiocese, for the theology department at St. Louis University and as a campus minister.