Sir Alex Ferguson says he understands why Jose Mourinho decided against making Ryan Giggs his assistant manager at Manchester United and told BBC Sport: "It is time Ryan stood on his own feet."

Ferguson said Giggs, who has left Old Trafford after 29 years with the club, has the necessary "steel" to forge his own managerial career away from the club.

Giggs, who spent his entire playing career with United, had acted as caretaker manager after David Moyes' dismissal and then served as assistant to Louis van Gaal during the Dutchman's two-year reign.

Mourinho, though, is expected to hand long-time assistant Rui Faria the role at Old Trafford, with a source telling ESPN FC last month that Giggs had rejected a different position on the coaching staff.

Ferguson, who managed United between 1986 and 2013, said he understood the new manager's reasoning.

"You have got to have, in your assistant, someone you have trusted all your life," Ferguson said. "When I came to United, I brought Archie Knox because he was a valuable person for me. I trusted him 100 percent.

"Jose Mourinho has had his assistant for years and, quite rightly, has stuck by his own man. If Jose hadn't had an assistant, I know he would have taken Ryan."

Giggs, who said Ferguson and Van Gaal had been "great managerial mentors," confirmed he hopes to take charge of a club in the future but said there are "no immediate plans" to do so.

Ferguson said Giggs had the right personality to thrive in management.

"It is time Ryan stood on his own feet, got out there and accepted the challenge," he said.

"I talk about his poker face. He has a bit of steel about him. It is such a highly intense results industry, you need people who go into it to have a bit of steel about them, a bit of character and personality."

Ferguson suggested that Giggs, who had previously been linked with Nottingham Forest, was simply waiting for an opportunity to manage at the right club.

"I think he is ready to manage and he has a lot of quality," Ferguson said. "He doesn't want to spoil that quality by going to a club where it is sacking a manager every two minutes."