Opponents of British Prime Minister David Cameron's bid to push through legislation allowing gay marriage attacked the bill on Tuesday ahead of a vote in parliament.
Cameron has championed the drive to allow same-sex couples to marry in England and Wales but faces the embarrassing prospect of seeing half his party's lawmakers opposing him in the vote which has created bitter divisions.
While the prime minister faces an uncomfortable evening, the outcome of the vote is not in question because the draft legislation has overwhelming support from the opposition Labour Party.
But pleas from Cameron's heavyweight cabinet allies to persuade their Conservative Party colleagues to back his plans and avoid damaging divisions fell on deaf ears.
A former junior defence minister, Gerald Howarth, said the government had no mandate for such a "massive social and cultural change".
"I believe this bill is wrong, the consultation was a complete sham. It has caused deep and needless divisions within the Conservative Party," he said during an impassioned debate on the bill in parliament ahead of the vote due at 1900 GMT.
He added: "There are many major issues this country has to deal with, this is an irrelevance."
Another Conservative opponent, Roger Gale, said the legislation was "Orwellian".
"Marriage is the union between a man and a woman, has been historically, remains so. It is Alice in Wonderland territory, Orwellian almost, for any government of any political persuasion to seek to come along and try to re-write the lexicon," he said.
A vote in favour would put Britain well on track to be the 11th country to allow gay couples to marry. Same-sex couples in Britain have had the right to live in civil partnerships since 2005.
Culture Secretary Maria Miller, the minister responsible for the legislation, insisted the bill would protect religious freedoms and "not marginalise those who believe marriage should be between a man and a woman".
The push to win over those Conservatives still bitterly opposed to gay marriage was led by three senior party members -- finance minister George Osborne, foreign minister William Hague and interior minister Theresa May.
In a letter to the Daily Telegraph, they said "attitudes to gay people have changed" and same-sex marriage was "the right thing to do at the right time".
There were signs that some of the Tory waverers were falling into line. Even Chris Grayling, a right-wing lawmaker who once defended the right of a bed and breakfast proprietor to refuse to admit gay couples, said he would back the legislation.
Grayling said in an interview with the gay magazine Attitude that the legislation was "a sensible next step" in the evolution of social attitudes.
The proposals are opposed by the Church of England and its new Archbishop of Canterbury Justin Welby, but the legislation bans the "official" churches from offering gay marriage.
If the bill is passed by the House of Commons, it must next be scrutinised by a committee of lawmakers and then go before the upper chamber the House of Lords before becoming law.
While a majority of people in Britain back gay marriage, polls show that Cameron's strong support for the issue could cost his party more votes that it wins at the next general election in 2015.
More than a third, 34 percent, said it made the Conservatives less attractive to them as voters, compared to 15 percent who said it made the party more appealing, according to the ComRes survey for ITV News.
The poll of 2,050 people also showed less support than previous polls for same-sex marriage.
Some 42 percent were in favour, against 40 percent who were not.
The issue has not however sparked the impassioned protests seen in France, where the National Assembly on Saturday overwhelmingly approved a key piece of legislation that will allow homosexual couples to marry and adopt children.