On top of the apology, the newspaper is rumoured to have paid out pounds 500,000 in damages to the American actress Brooke Shields.
Last week, the Mail on Sunday had reported that Ms Shields was being held by French police on suspicion of possessing drugs. The newspaper claimed that a flight from Nice to Paris had been delayed for two hours while the aircraft and Ms Shields were searched. But the fact that no other tabloids followed up such a good story last Monday indicated that all was not right with the tale.
And yesterday, despite claiming that it had checked its original story, the Mail admitted that: "There was no airport swoop; Miss Shields was not stopped at the airport; was not searched; was not quizzed; did not have any drugs or other illegal substances in her possession; has not and does not use drugs, and that there were never any grounds even to suspect that she had done so."
As well as the apology, the newspaper has promised to pay a "very substantial sum" of damages and legal costs to Ms Shields or a charity of her choice. Rumours at the Mail put the figure at close to pounds 500,000.
The Mail yesterday was po-faced in the extreme after Ms Shields' lawyers, Schilling and Lom and Partners, began libel proceedings against the paper's publishers, its editor Jonathan Holborow and the two reporters who wrote the story.
Mr Holborow even went so far as to apologise personally to the actress and repeat the apology on the top of the newspaper's page three.