Senior figures in the Church of England have supported a Christian counsellor who treated a gay man when he asked to be cured of his homosexuality.

Lord Carey, the former archbishop of Canterbury, as well as Bishop of Chester the Rt Rev Peter Forster, and Bishop of Lewes the Rt Rev Wallace Benn were among signatories to a letter giving support to 60-year-old psychotherapist Lesley Pilkington.

The counsellor is due to mount an appeal this week following a British Association for Counselling and Psychotherapy (BACP) ruling that she was guilty of professional misconduct over a therapy session with gay journalist Patrick Strudwick.

Working undercover, Strudwick approached Ms Pilkington and asked her to "make me straight" after meeting her at a conference for therapists and psychiatrists who wanted to learn how to convert their patients to heterosexuality. Writing in The Guardian last year, he said:

"I am an out, happily gay man. I was undercover, investigating therapists who practise this so-called conversion therapy - also known as reparative therapy - who try to 'pray away the gay',"

"I asked her to make me straight.

"Her attempts to do so flout the advice of every major mental-health body in Britain."

In their letter, the clerics said Ms Pilkington distinguishes "very carefully" between her "non-directive" counselling and the biblical and pastoral counselling she also offers as a Christian.

"We believe that people who seek, freely, to resolve unwanted same-sex attractions hold the moral right to receive professional assistance," they said.

"Whether motivated by Christian conscience or other values, clients, not practitioners, have the prerogative to choose the yardstick by which to define themselves.

"Not everyone stakes their identity on sexual feelings."

Mrs Pilkington has claimed the BACP hearing against her was unfair and discriminated against her Christian faith.