Paisley MP Mhairi Black has apologised after a video emerged appearing to show her boozing on a Glasgow train.
The SNP politician "has been reminded of the rules" by party chiefs after the footage was first published last night.
It is believed she was travelling back from a football match between Ayr United and Partick Thistle at the time, the Daily Record reports.
It is currently forbidden to consume alcohol on ScotRail trains, and the video, first published by The Spectator, shows what looks like the MP for Paisley and Renfrewshire South swigging from a can of what appears to be lager.
The booze ban on trains had been put in place as a "temporary measure" to prevent transmission of Covid-19 in November 2020.
However, it was extended for 17 months when ministers took over the rail operator on April 1.
It means passengers are currently unable to bring their own alcoholic drinks on trains or purchase them from staff.
Additionally, the MP is also without a mask in the clip while officials continue to recommend the use of face coverings during Covid-19.
An SNP spokesperson said: "Mhairi has been reminded of the rules and apologises."