Manchester United are unhappy with Brentford despite finally signing Bryan Mbeumo in a £71million deal following weeks of haggling.
United will pay a fixed fee of £65m with £6m in potential add-ons for Mbeumo who has agreed a five-year contract with the option of another year.
The 25-year-old Cameroon forward, who is now set to go on United's pre-season tour to the US, said: 'As soon as I knew there was a chance to join Manchester United, I had to take the opportunity to sign for the club of my dreams; the team whose shirt I wore growing up.