The 71-year-old first announced he would retire from the game in 2002, but he remains in charge at Old Trafford and has lead the side to the top of the Premier League table this term, where they hold a 12-point advantage over Manchester City.
Asked when he intends to finally step down, Sir Alex told reporters: "There's no getting rid of me, I will probably become director.
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Jose Mourinho, Pep Guardiola and David Moyes are thought to be among the favourites to replace Sir Alex when he does depart the dug-out and after over a quarter of a century in the job, the Scot expects to have a hand in selecting his successor.
"They'll ask me. But I think it'll be a club decision not mine," he explained.
The United boss also hailed the players within his current squad that could go on to take charge of the club, once they are ready.
He said: "Looking at my present crop, it's difficult, but the likes of [Ryan] Giggs and [Paul] Scholes will be part of the structure here. Darren Fletcher in the long term possibly and Nicky Butt is with the reserves.
"We try to get as many former players in the set-up as we can; we've got a good back-up.
"We look ahead because that is succession planning in terms of structure - they've the experience of being at the club, being a player here, knowing what it takes to be a winner. It's good to have it here, keep it within the club."