It is understood personal terms have been agreed between Jose Mourinho and Manchester United, who need to finalise issues such as image rights before the deal can be formally announced.
United were hopeful of making an announcement to confirm Mourinho’s appointment on Wednesday, but the complex nature of the contract details means it could be Thursday before the deal is confirmed.
The Portuguese was pictured walking in London late on Tuesday night, flanked by his bodyguard, and was captured checking his mobile phone.
Mourinho is said to have instructed United’s executive vice-chairman Ed Woodward to sign a new centre-back, right midfielder, central midfielder and centre-forward, with free agent Zlatan Ibrahimovic set to be the striker.
The incoming United boss is understood to want a “captain” in central midfield.