Dozens of women clergy and hundreds of lay members could leave the Church of England if plans to restrict the powers of women bishops are approved.

Supporters of women priests said that female clergy and even male clergy could defect to the Methodist or Lutheran churches.

They could also go to Scotland, a liberal province of the Anglican Communion where two dioceses are seeking new bishops. It is believed that one could make history by electing Britain’s first woman bishop. Some might even emigrate to the United States, which, with Canada and Australia, already has women bishops.

Congregations could move as well, it is feared, as happened when women were ordained priests and Anglo-Catholics defected to the Orthodox or Roman Catholic churches. This would mean a loss to the Church of England of many thousands of worshippers. Many women, disillusioned with the male-dominated hierarchy, could also decide to stop going to church at all.

The Church of England’s General Synod voted in 2006 to remove legislative obstacles to women bishops and accepted that having women bishops was consistent with the faith of the Church in 2007.

In February a revision committee was appointed to find a way to legislate for women bishops without causing the Church’s remaining traditionalists to defect.

Hundreds of women protested to the lobby group Women and the Church after the revision committee published proposals last week for statutory powers to restrict the powers of women bishops in order to placate traditionalists.

Under the plans, a new tier of “super flying bishops” would be created to operate outside the authority of a diocesan bishop. They would be able to offer pastoral care such as confirmations and ordinations to the opponents of women’s ordination.

Such an arrangement would be unprecedented at episcopal level and has been criticised by women because it creates a two-tier Church, with women bishops in effect regarded as tainted or of “inferior” order.

Christina Rees, a national organiser of Women and the Church and a member of synod, said: “This is the last straw. This has caused an implosion of confidence in the Church’s attitude to women. Women clergy are very unhappy and rarely before have I heard such scathing comments. Dozens could leave.”

Of 10,000 serving clergy in the Church of England, about 3,000 members are women.

Sally Barnes, of London, said: “There is a huge amount of anger. Quite a few women are asking why they should bother any more. It seems that it is not OK to be racist, but it is OK to be sexist.”