have rejected a £54million offer from Inter Milan for Romelu Lukaku
News of the bid came just hours before the two clubs were due to play each other in the International Champions Cup in Singapore.
The offer is thought to include add-ons but was knocked back by United. They are prepared to sell Lukaku but are looking to recoup the total fee of £90million they agreed with Everton two years ago.
Lukaku has been ruled out of the game with the unspecified injury that meant he couldn't play in the first two games on United's pre-season tour.
On Friday, Inter boss Antonio Conte confirmed his in signing Lukaku, describing the 26-year-old as an 'important player' in his plans for the new season.
Conte was Chelsea coach when they lost out to United in the race for Lukaku in 2017, and he is starting to grow impatient with Inter's failure to sign him this time.
The Italian, who is without any recognised strikers on tour after telling Mauro Icardi that he is no longer part of his plans, said: 'I think frustrated is a big word.
'Lukaku is United's player and this is the reality. You know very well that I like this player, also in the past when I was Chelsea's coach and tried to bring him to Chelsea.
'I think that in this moment if you're talking about a player from another club it's right to not talk about Lukaku because we have great respect for United.
'As I said before, I like this player and consider him an important player for us to have a good improvement, but at the same there is a transfer market.
'We know very well what is our situation at the moment and we will see what happens, but for now Lukaku is a United player.
'It's not easy to play against teams like Juventus and Manchester United without a striker, but the market is open so there is still a process for players to come in and out.' United boss Ole Gunnar Solskjaer admitted that Lukaku will miss his third game in a row on tour after sitting out the first two friendlies against Perth Glory and Leeds United.
'No, he's not fit so he won't be available,' said Solskjaer. 'I don't have any updates from the last time I spoke to you.
'Luke (Shaw) has missed a couple of days, training Anthony (Martial) one day and Romelu is the one who has missed them all.'