Manchester United manager Jose Mourinho has revealed that he could be missing three of his South American contingent for the derby match against Manchester City next Saturday.

The bulk of United's squad will return from international duty throughout the week building up to the eagerly-anticipated meeting between the two rivals, which will also see Mourinho come face to face with Pep Guardiola once again.

However, Sergio Romero, Marcos Rojo and Antonio Valencia - the latter of whom has started all three games for United so far this season - will not return until the day before the crunch match at Old Trafford.

"We keep eight outfield players and Sam Johnstone as the goalkeeper [for training]. We are going to lose the others and we don't know the way they train, the way they recover, the life they are going to have with their national teams," Mourinho told the club's official website.

"Some are coming back on the Monday before the Manchester City match but some are coming back on Friday. The day before Man City, we will still have Sergio Romero, Marcos Rojo and Antonio Valencia arriving.

"It will be a complicated process but we know it is like this when we have these players. And I would love all of the players to go because it would mean that everybody is being selected for their national teams."

The Manchester rivals are two of only three teams to have won their opening three games of the Premier League season, alongside Chelsea.