The Red Devils travel to Tottenham on Sunday looking to avenge their 3-2 defeat from earlier this season, and will face Gareth Bale, a player with a reputation for diving having picked up three bookings for simulation already this term.
The 71-year-old believes Andre Villas-Boas is responsible for his players' actions, and accordingly must warn Bale about diving just as the United boss himself did with Cristiano Ronaldo and Ashley Young.
"This was raised at the League Managers’ Association meeting during the week,” Sir Alex told The Mirror.
"What are the sanctions on that? Do they come from the club or do they come from the FA?
"I think the FA have a problem because is it legal what they do? Can they prove that a lad has positively tried to dive?
"It’s a very difficult one. They’ve always said that, haven’t they? They have no sanctions on diving.
"So, does it go to the club? At the end of the day it probably does. You have to [warn players if they dive]. I’ve done it with Cristiano [Ronaldo].
"He was only a young boy, 18, when he came here and it took him maybe a couple of years to understand that. But after that he was fine."Liverpool's Luis Suarez admitted to deliberately diving earlier this week, and Sir Alex believes the Uruguayan could now face an FA misconduct charge.
"That’s different," added the United manager. "They could take action on that, but I don’t have any views on that myself, to be honest.
"I don’t know much about the interview, other than what I’ve read - in the sense he’s admitted he dived. But that’s a different issue altogether."