The 27-year-old forward was left out of the last two Red Devils matches in order to recover from a muscle problem he picked up while on international duty with England.
Ferguson has insisted there was no need to risk further damaging the injury by bringing the striker back too soon, but has said that he is line to face City, who trail United by 15 points at the top of the table, on April 8.
He said: "He got a groin injury playing for England. He wasn't 100% and there is no point risking players with groin injuries.
"It could exacerbate itself and you could be out for weeks. Hopefully he will be ready for next Monday's game."
Rooney has scored 16 goals in 30 United appearances this season.