Manchester United's Sir Alex Ferguson, British football's most successful manager, is retiring after 26 years. Everton's David Moyes and Jose Mourinho of Real Madrid are front-runners to succeed him.

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Ferguson, 71, will step down from the club at the end of the season, following the match against West Bromwich Albion, and will become a Man Utd director and ambassador.

Announcing his decision to retire, Sir Alex said: "The decision to retire is one that I have thought a great deal about and one that I have not taken lightly. It is the right time.

"It was important to me to leave an organisation in the strongest possible shape and I believe I have done so. The quality of this league winning squad, and the balance of ages within it, bodes well for continued success at the highest level whilst the structure of the youth set-up will ensure that the long-term future of the club remains a bright one."

Tough act to follow

After his 38 trophy-winning success at Old Trafford, Sir Alex will be a tough act to follow. Former Man Utd midfielder told MUTV: "Everybody will be a little bit concerned. Can the next guy coming through the door do what Sir Alex has done? That's going to be tough."

Former Man Utd striker Dwight Yorke told Sky Sports News: "For him not to be there from the start of next season, it's not going to be right around the football club and it will take some getting used to."

Paying tribute to Sir Alex on Twitter, Prime Minister David Cameron said he hoped his retirement "will make life a little easier for my team #AVFC".

Labour leader Ed Miliband tweeted that he was a "staunch" supporter of his party, while former deputy prime minister Lord Prescott used Twitter to thank Sir Alex for "helping the reds in football and politics".

Who will take over?

Betting companies were quick to cash in on the inevitable speculation as to who will take over from "Fergie".

Paddy Power and William Hill had former Chelsea manager and current Real Madrid boss Jose Mourinho at evens, with Everton manager David Moyes at 5/4 and Borussia Dortmund manager Jurgen Klopp in third.

Sir Alex, who with 49 trophies to his name is the most successful manager in British footballing history, had been subject to speculation in British newspapers on Wednesday. The reports were based on rumours that emerged at a team golf day on Tuesday.

Man Utd are usually quick to shoot down stories they believe are wrong. However, the club had remained silent when the rumours emerged.

As the club are listed on the New York Stock Exchange, they are obliged to announce significant news to the market.

Before Utd floated on the stock exchange last year, their American owners, the Glazer family, warned that any change in manager could damage the club.

A prospectus for the share issue said: "Any successor to our current manager may not be as successful as our current manager. A downturn in the performance of our first team could adversely affect our ability to attract and retain coaches and players."

Sir Alex's future as manager had been called into question in the past. In 1989, he was expected to be sacked and in 2002 he was about to retire, but performed a last-minute U-turn.

13th title

After winning his 13th Premier League title two weeks ago, Sir Alex denied he had any plans to step down.

"I certainly don't have any plans at the moment to walk away from what I believe will be something special and worth being around to see," he said.

However, it emerged at the weekend that the 71-year-old manager requires hip surgery. In the past he has said that only health problems would force him into retirement.

Utd chief executive David Gill said after the latest title triumph that Ferguson had "not knocked on my door" and said he wanted to retire.

However, Mr Gill did also say that any new manager would have to adapt to the existing squad and support team rather than making radical changes.

"The quality of the squad, the composition of that squad, means that any new manager coming in will inherit a great squad of players," he said. "And yes he may, whenever that is ... clearly want to bring in one or two of his own people, new players.

"But he won't want to change the squad wholesale because he won't be our manager. We've got to be consistent with that and that's what we are planning on."

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