Sir Alex Ferguson believes foreign players dive more than their British counterparts in the Premier League.
Ferguson was responding to comments made by Manchester City striker Sergio Aguero on Sunday that British players received "privileged" treatment from referees.
Earlier, Liverpool manager Brendan Rodgers stated Luis Suarez had a penalty claim waved away because of his reputation, and Ferguson was inclined to agree.
The United boss believes Nani should also have been awarded a spot-kick after tangling with Jan Vertonghen in Saturday's loss to Tottenham, and defended the winger over claims of diving before suggesting foreign players have been particularly guilty of diving in the past.
"Nani is not the type to dive, I know that," said Ferguson. "It was a penalty kick on Saturday. Sometimes you get them, sometimes you don't. The linesman could have helped, but didn't.
"But it's not worth going into that subject, because down the years there have been plenty of players diving and, you have to say, particularly foreign players."
United will take on CFR Cluj on Tuesday evening. After arriving in Romania, Ferguson was greeted by local media claiming the Premier League side were "arrogant". But the Scot says his side will not take their Group H opponents at the Dr Constantin Radulescu Stadium.
"Cluj defend quickly and get plenty of bodies behind the ball, but their main strength is counter-attack, as they showed against Braga.
"Counter-attacking has become a very important part of European football. Now it's done by four or five players, not one or two like 20 years ago," he said.