A DUP MP photographed while not wearing a face mask on the London underground has complained the UK is becoming “East Germany under the Stasi”.

Sammy Wilson was snapped on the tube without a covering by a member of the public.

He acknowledged that he was wrong not to have worn a mask but condemned the photographer for acting like a “snoop”.

In a statement to the PA news agency, Wilson queried why the person who took the photograph had not approached him directly on the train.

"I didn't have a mask on, should have had it on and am offering no excuse but it is sad that we have now become like East Germany under the Stasi where members of the public think it is acceptable to act as snoops," he said.

"Whoever took the picture didn't approach me or say anything to me which I suppose would have been the proper way to behave."

READ MORE: Tory MP apologises after he 'forgot' to wear mask on a train

Those caught not wearing a covering on public transport in London can face a £200 fine, which doubles each time a person is caught, up to £6400. There are exemptions for the rule on the basis of age, health and disability reasons.

Asked about the incident at the Stormont Executive press conference, DUP leader Arlene Foster has said everyone is "equally subject to the law".

She commented: “Sammy has made a statement in relation to that matter. But just for clarity, I want to say this as clearly as I can, everyone is subject to the law, everyone is equally subject to the law and equal under the law.

"So it is important that we remember that, and that is the position of the DUP."

Wilson has previously been outspoken about the wearing of face coverings.

In July he tweeted a photograph of himself in an ice cream shop in Co Antrim not wearing a mask, with the message "you can't eat ice cream when you're muzzled!"

Face coverings in indoor places became compulsory in Northern Ireland on August 10.