The Belgian striker spoke to media outlets in Los Angeles before the club unveiled him as their new £75million signing from Everton, report the Manchester Evening News .
This came ahead of the club’s planned announcement, which included a photoshoot and exclusive interview with MUTV.
However, Lukaku, who was on holiday in LA with his friend and new team-mate Paul Pogba, spoke to two outlets a time when his move was still to be finalised.
It’s understood the 24-year-old did not receive censure from United officials or Mourinho, with the club accepting he will have been led by his own representatives.
And despite the club being gazumped on their own exclusive, they were at least relieved there was little in the way of embarrassing content – Lukaku instead speaking in glowing terms of his new employers.
He did however reveal what number he asked to wear at United – again before a decision had been officially made.
The striker revealed he’d spoken to Zlatan Ibrahimovic about wearing No9 when interviewed by ESPN.
“Strikers play with No. 9,” he said. “It’s a nice number, and I asked the permission of Zlatan Ibrahimovic.
“I want to thank him, as well, for allowing me to wear that number.”