Sadiq Khan's Transport for London has found itself at the centre of a fresh row after a series of pro-assisted dying campaign adverts started appearing on the Tube.
The ads, for campaign group Dignity in Dying, are part of a push on MPs to vote through Kim Leadbeater's controversial assisted dying Bill ahead of its first debate in the Commons on Friday, November 29.
Inside Westminster Underground station, right next to the Houses of Parliament, an entire corridor has been decked out with the billboards - which has since been dubbed the "Westminster Death Tunnel".
All of the ads centre on the campaign message "my dying wish" - for example, one shows a photograph of a smiling woman named Sophie with the caption: "My dying wish is my family won't see me suffer - and I won't have to."
Part of one Underground station has been dubbed the 'Westminster Death Tunnel'
FLEUR ELIZABETH
All of the ads centre on the campaign message 'my dying wish'
DIGNITY IN DYING
But the transport body's rules say that advertisements which reasonably promote non-party-political causes will not normally be disapproved.
Voting on the assisted dying Bill is set to be free and not whipped - which could explain its approval for use on the Underground.
Writing against the ads for UnHerd, commentator Niall Gooch said the ads' intention "is clearly to make people who do not know much about end-of-life care - a large majority of the population - assume that without assisted suicide, we are all at high risk of an unpleasant death, pointlessly prolonged by dogmatic vitalist medical professionals.
"But this is not the case. British palliative care is some of the best in the world, and patients already have the right to refuse medical interventions," he added.
'Who at TfL thought it was remotely appropriate to promote assisted suicide on the London Underground?' Adrian Hilton asked
PA
Dignity in Dying says: "For too many dying people right now, their dying wish is simply for choice and control at the end of their life.
"If passed, Kim Leadbeater MBE MP's Bill will mean that, finally, their wishes - our wishes - can be respected.
"It's time for MPs to let us choose. Together we need to show them why they must vote Yes to the choice at the end of life bill and legalise assisted dying for terminally ill, mentally competent adults.
"That’s why we’re taking dying wishes to the heart of Westminster."
GB News has approached TfL, the Mayor of London, Global, and Dignity in Dying for comment.