Tony Blair has cast doubt on whether Labour can win the general election operating on Ed Miliband's "traditional left-wing" platform.
The Labour former prime minister predicted a Tory win in the event of a traditional left-right battle in 2015 and stressed the importance of "not alienating large parts of business, for one thing".
In an interview with the Economist, Mr Blair called on his party to revive the spirit of "New Labour" and move into the centre ground in order to win the May election.
Mr Miliband has committed his party to what many commentators see as left-wing policies, including the freezing of energy prices and the reinstatement of the 50p top rate of income tax.
Mr Blair told the Economist the election could be one "in which a traditional left-wing party competes with a traditional right-wing party, with the traditional result".
Asked if he meant a Tory win, Mr Blair replied: "Yes, that is what happens."
In what could be seen as an attack on Mr Miliband's leadership, Mr Blair said Labour performs best when it is occupying the centre ground.
He said: "I am still very much New Labour and Ed would not describe himself in that way, so there is obviously a difference there.
"I am convinced the Labour Party succeeds best when it is in the centre ground".
Mr Blair also cast doubt on Mr Miliband's claim that the financial crash of 2007/8 and subsequent worldwide economic meltdown has shifted Britain's political centre ground towards the left.
The former PM said: "I see no evidence for that. You could argue that it has moved to the right, not left."
Mr Blair won three elections for Labour after modernising the party, abolishing its commitment to nationalisation and openly courting big business.