Shaun Woodward, the party's spokesman on London, was fired after he refused to back the party line to retain a ban on the "promotion" of homosexuality by councils.
The Conservatives decided last week to oppose vigorously government plans to repeal the controversial section 28 of the Local Government Act. Mr Woodward, a consistent advocate of homosexual equality, refused to obey the party's three-line whip on the policy.
The MP for Witney was given a deadline of 6.30pm to change his mind and was fired after he refused to assure the Chief Whip, James Arbuthnot, he would not vote with the Government. Mr Woodward's main objection was that section 28 prevents teachers from taking action to stamp out homophobic bullying in schools.
The Tory leadership offered a compromise, which would retain the section while amending it to exclude bullying, but he refused to take up the deal.
In a letter to Mr Arbuthnot, Mr Woodward said he was "extremely sorry" the party had chosen to fire him but "as a matter of conscience" he thought the legislation discriminatory. The MP, who is a director of the ChildLine charity, said he could not support anything that would perpetuate the bullying of schoolchildren unsure of their sexuality.
Mr Woodward, who pointed out that his stance was backed by child protection agencies, the Royal College of Nursing and the Family Planning Association, said section 28 "simply causes more harm".
A Tory source said: "William [Hague] was not personally involved in the discussions with Mr Woodward but he fully supported the Chief Whip's action."
Peter Tatchell, of the homosexual rights group OutRage!, said the sacking was proof that the Tories were unwilling to tolerate dissent or move forward towards more gay-friendly policies.
The controversy follows research published last week that accused Mr Hague of bolstering "outdated" views on women by excluding them from his drive to modernise the party.Reuse content