Lily, 31, recently visited those living in the now-demolished Calais jungle to volunteer in a charity warehouse and she hit the headlines after saying to a 13-year-old boy: "I apologise on behalf of my country. I'm sorry for what we have put you through."
While in London with her children on Friday, however, singer Lily claims she was verbally abused and "discriminated against" while hailing down a black taxi.
Taking to Twitter, she told her 5.8 million followers: "Just tried to get in a black cab with my kids. The driver looked at me and said, 'Find an immigrant to drive you, you stupid tart'.
"Having lived a life of privilege, that interaction has given me a tiny glimpse of what it feels like to be discriminated against."
Just tried to get in a black cab with my kids. The driver looked at me and said , 'find an immigrant to drive you you stupid tart'— lily allen (@lilyallen) October 28, 2016
She added: "There is so much work to be done. But we can do it. Let's stamp out this stupid horrible ignorance together. #takeourcountryback."
Many of Lily's followers were quick to reply to her posts, with one question her claim and asking if she managed to get the registration details of the alleged cab involved. She replied: "I had both my hands full with children, couldn't get to my phone fast enough."
Lily has been very outspoken about her feelings surrounding those who were living in the Calais jungle camp in France, which was pulled down earlier this week.
But after her conversation with the Afgan teenager - who had tried to jump on lorries to get to his father in Birmingham - was caught on camera, she found herself under scrutiny by some and branded "indulgent".
Writing a piece for Vice.com, Lily later hit back: "I went to Calais because I wanted to do what I can to help. I wanted to try to remind people of the humanity at the heart of the crisis, at a time when refugees were being demonised in the press."
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