Sir Alex Ferguson arrives at work amid speculation on his future
Sir Alex Ferguson has arrived at Manchester United's training ground amid speculation he may retire.
United are yet to comment on the widespread rumours in national newspapers on Wednesday morning.
The Scot, 71, saw his team win the Premier League title 17 days ago to take the number of trophies he has won in 26 years at United to 38.
His haul includes 13 titles, two Champions League crowns, five FA Cups and five League Cups.
BBC Sport's Dan Roan said: "The club have made no official comment confirming or denying the story.
"But they have a listing on the New York Stock Exchange and need to give clarification on any information that affects the running of the club.
"I think they will be making a statement in the next couple of hours."
Ferguson, who took over from Ron Atkinson on 6 November 1986, has always said he would carry on as long as he stayed healthy but he had a heart pacemaker fitted in 2004 and faces a hip replacement operation in August.
He gave no indication he was thinking over his future in Sunday's programme notes against Chelsea when he said: "I certainly don't have any plans at the moment to walk away from what I believe will be something special."
But rumours filtered out after the club's end-of-season players versus coaches golf day at Dunham Massey on Tuesday afternoon.
Bookmakers have made Everton manager David Moyes odds-on favourite to take over at Old Trafford.
The Scot is out of contract in the summer at Goodison Park and has delayed talks on a new deal until the end of the season.
The United manager arrived at work at the club's Carrington training ground at 06:50 BST on Wednesday without stopping to talk to a group of waiting reporters.
If he leaves United, Ferguson will exit the club with 15 members of the first-team squad aged 23 or under.
Ferguson is confident they have the potential to provide the backbone of the United team for years to come.
"You have to look at the structure of the club at present, in terms of the number of first-team players we have at 23 or under," he said recently.
"We have been targeting the players that we feel could enhance us, make us better or help us maintain the level we're at."