The main group campaigning against equal marriage in the UK has used another Conservative MP’s photograph on its publicity leaflets without her permission.

Anne Milton, the MP for Guildford in Surrey, is said to be “furious” with the Coalition for Marriage (C4M).

According to GetSurrey.co.uk, Mrs Milton, a former health minister and now a government whip, said she was “absolutely on the ceiling” with anger after discovering that C4M have been delivering leaflets with a picture of the MP to residents in her constituency.

Mrs Milton said: “I am very angry about this because I have been contacted by several constituents claiming that I am in fact campaigning against gay marriage, which is simply not the case. I do not endorse the views of the Coalition for Marriage and I have not formed an opinion on this subject at this time, nor has the Conservative Party. I am keen to hear the views of my constituents.”

She added: “The gay marriage issue is one that many people feel very passionately on and that is why I am keen to hear as many views as possible from people. I have no strong opinion in either direction at this time and I certainly would not want people to think otherwise.”

Earlier this month, C4M angered Sarah Newton, the Conservative MP for Truro and Falmouth, by using an image of the MP on its campaigning leaflets, ahead of a local equal marriage debate in her constituency.

Ms Newton said she was angry at the misrepresentation and intended to seek legal advice.

A spokesman for the Coalition for Marriage said: “Our organisation is not representative of any political party or group. All our leaflet intends to do is urge people to contact their local MP and share their views.

“This is a widely accepted practice, something that is done for all sorts of things, such as a planning application. This is part of the democratic process and we have no intention of changing something that is completely standard practice and used all over the country.”

MPs will vote on the second reading of the government’s Marriage (Same Sex Couples) Bill on Tuesday 5 February.