Tim Mason has said he will not succeed Sir Terry Leahy as chief executive of Tesco.

Mason, who is chief executive of the retailer’s US operations and Leahy's second in command, has ended years of speculation that he will take over the role.

He ruled himself out during a visit to some Fresh & Easy stores in the US, according to The Financial Times. Mason said the role will go to a younger candidate.

The former Tesco marketing executive had been expected to succeed Leahy when he was picked to launch Fresh & Easy in the US.

Mason, who is 50, said he was too old to succeed Leahy, given that Leahy – who is 51 years old – is expected to stay in the job for another five years or more.

Mason said there was a pool of internal talent at Tesco, but declined to comment on who might take over.

Part of Tesco’s success has been maintaining a stable senior team during Leahy’s tenure. Five of the seven executive board directors have been in place for nearly 10 years.

However, there has been a recent spate of departures from the 60 or so executives that sit below the Tesco board, including operations director John Browett, who has become chief executive at electricals giant DSGi.

Tesco international director Phil Clarke and trading director Richard Brasher reportedly have their eye on the chief executive role. However, it is expected that Tesco will appoint someone who is young enough to sit through a 10-year tenure before reaching the age of 60. Clarke is 47 and Brasher is 45.