Conservative MP and former party leader Iain Duncan Smith has come to the defence of Maria Miller over recent expenses inquiries, saying she is facing a possible Tory backlash for “the gay marriage stuff.”

Speaking on the BBC’s Andrew Marr Show, he said he considered the Culture Secretary to be a “reasonable and honest person.”

“I think she has done a very good job in a very difficult set of circumstances, with the Leveson Inquiry, which has stirred up a lot of media antipathy to her.”

Mrs Miller was recently ordered  to repay £5,800 and apologise to MPs after over-claiming expenses on her mortgage.

He added: “And also the gay marriage stuff – there’s a lot of Conservatives out there who perhaps weren’t necessarily supportive, also feel rather bitter about that. In a sense, she is also receiving some of that as part of this process.

“My view generally is that I’m supportive of Maria, because if we are not careful we end up with a witch hunt of somebody.”

The Minister for Women and Equalities was responsible for steering the government’s same-sex marriage legislation through the Commons.

In a PinkNews article last week, Mrs Miller reiterated a promise to allow couples in civil partnerships the option of converting them to marriages by the end of the year.

“I’m very much aware that there are couples who are already in a civil partnership and who may be disappointed that they will have to wait a little longer to be able to convert to a marriage. I’d like to reassure them that we are working hard to ensure that this process is in place by the end of year,” Mrs Miller said.