A letter to Rowan Williams, the archbishop of Canterbury, and John Sentamu, the archbishop of York, was signed by 1,300 members of the clergy, The Times of London reported. About 10 percent of the active clergy and hundreds of retirees are among the signers.

The synod, which begins Friday in York, is expected to vote on whether women should be allowed to serve as bishops.

Another vote would determine whether those who disagree would be allowed to have a network of churches with an exclusively male clergy. To complicate matters, another group has said it opposes any special facilities for those who do not support women in the priesthood.

The disagreement in the English church comes as the worldwide Anglican communion threatens to split over homosexual priests. A group of conservatives met in Jerusalem last week and decided to set up a parallel structure that would remain Anglican but would not recognize Williams' authority.

Williams in a statement, warned the dissidents to think carefully about what they are doing, The Telegraph said.