Shadow Home Secretary Diane Abbott has apologised after a photo emerged of her sipping a mojito on a London Overground train.
Since 1 June, 2008 it has been illegal to drink alcohol on Transport for London’s (TfL) network.
The Hackney North and Stoke Newington MP said she was “sincerely sorry for drinking on TfL”.
Under TfL’s conditions of carriage “anyone caught consuming alcohol may be prosecuted”.
Ms Abbott said she was “sincerely sorry” for drinking the Marks and Spencer cocktail.
She wrote on Twitter: “A photo of me drinking from a can of M&S mojito on the Overground has been circulated.
“I’m sincerely sorry for drinking on TFL.”
Ms Abbott received several supportive messages in reply to her tweet, with one Twitter user writing: “I’m sincerely sorry you feel the need to say sorry Dianne and i hope you really enjoyed the drink it’s no one’s business but yours.”
Another said: “Put it in a water bottle next time.”