Redefining marriage could lead to people who believe in traditional marriage being accused of ‘hate crimes’, UKIP’s openly gay London Regional Chairman has warned.

David Coburn, who is also a London Assembly candidate, also said that rewriting the definition of marriage would represent an “unnecessary victory roll” by homosexuals.

Writing on a homosexual news website Mr Coburn said that UKIP “thoroughly supports equal rights for same sex civil partnerships”.

But he said his party was opposed to the Government’s plans to change the meaning of the word ‘marriage’.

He said: “If the government does legislate in this way UKIP believes that any criticism of same sex marriage which may be expressed by someone on the basis of their faith could be classified as a ‘hate crime’.

“That would be a grotesque assault on people’s freedom of conscience. As we all know these things tend to be the thin end of the wedge once the government’s ludicrous overpaid/over-pensioned thought police get on the job.

“I have always fought for equal treatment and I believe civil partnerships have achieved that. However, I think it does the gay community no good whatever to cross the street and pick a fight with people of faith.”

Mr Coburn’s comments come as the Government launched a consultation on redefining marriage.

A petition supporting the current definition of marriage has already attracted more than 180,000 signatures. It is being run by the Coalition for Marriage.

Last week a poll revealed that 70 per cent of the population support man/woman marriage.

Meanwhile, a senior Labour member of the House of Lords has warned that redefining marriage could have “Orwellian” consequences.

Lord Brennan, who is also a leading QC, said that English law could refer to fathers and mothers with terms like “Progenitor A” and “Progenitor B” if marriage is redefined.

Writing in The Daily Telegraph, he cited evidence from countries that have already legalised same-sex marriage, which he said led to the erosion of terms such as ‘husband’ and ‘wife’.

He argued that such a move would require amendments to laws dating back to 1285. The remarks come as the Government prepares to launch its consultation on redefining marriage.

He said, “familiar words such as ‘husband and wife’ and ‘mother and father’ are disappearing from the statute books in the small minority of countries that have begun the experiment in social engineering”.

He went onto explain that, in Spain, marriage was redefined in 2005 and, “the following year, it was announced that Spanish birth certificates would read ‘Progenitor A’ and ‘Progenitor B’ instead of ‘father’ and ‘mother’.

“This kind of language is Orwellian. Can we expect the same kind of thing here if marriage is redefined?”

The Labour Peer also said David Cameron should be focussing on more pressing issues like the economy.

He said: “Given our present economic situation, why does Mr Cameron think that so much parliamentary time and energy should be dedicated to a change in the law which would obliterate vast amounts of our cultural and legal heritage?”

The QC added: “The change has rightly been described as ‘a profoundly radical step’ and to pursue it without any manifesto commitment is remarkable”.