The former Archbishop of Westminster, Cardinal Cormac Murphy-O’Connor, has questioned whether David Cameron can be trusted due to his support for equal marriage.

His comments came in a letter to the Telegraph, a day after almost 60 MPs and peers also signed a letter pledging to oppose the government’s marriage reforms.

The senior Catholic said the move was an “abuse of language” which he claimed would ultimately weaken the institution of marriage.

He also dismissed Mr Cameron’s argument that allowing gay couples to marry was a fundamentally “conservative” principle as “hollow”.

“Redefining it as simply a contract between individuals irrespective of their sex, without regard either to its procreative function or to the complementarity of the relationship between man and woman, would be an abuse of language,” he said.

“More important, it would weaken marriage by diminishing its implications and therefore its significance”.

In May, the current Archbishop of Westminster, the Most Reverend Vincent Nichols, warned of “damaging consequences” to society, and of severing the bonds which bring it together, if equal marriage was introduced in the UK.