The script for the high-profile advertisement had been signed off, the star had been hired and the creative team at the Irish sports betting company Paddy Power was convinced it had scored a win ahead of a big sporting summer.
Even with his back turned, and even before the big reveal, the man in the No. 10 England soccer jersey would be instantly recognizable by his build and shock of light hair: Boris Johnson.
“I told you I would get us back in Europe,” the script called for Mr. Johnson to say, a glib — and untrue — quip from a man who helped lead the Brexit campaign that resulted in Britain’s exit from the European Union.
But the ad will never air.
Paddy Power, which is headquartered in Dublin, was forced to scrap the planned clip — intended to be the cornerstone of its advertising campaign for a busy summer that will include the European soccer championship and the Paris Olympics — after a backlash from its staff in Britain.
The decision was confirmed by two people familiar with the campaign and its demise. They said a script for the ad had been provided to Mr. Johnson. A spokesman for Mr. Johnson did not respond to a request for comment.
