David Cameron has been embarrassed by his favourite think-tank after it suggested that Liverpool, Sunderland and Bolton should be abandoned because the North would never improve.

The Tory leader, who begins a two-day tour of the North today, firmly rejected a report by Policy Exchange, which suggested that the Government should help northerners to relocate to Oxford and Cambridge. It suggested that Britain’s two university towns are likely to be able to “form the basis of strong, successful, substantial cities”.

Singling out Sunderland as an example of a town in decline, the report says: “It is time to stop pretending that there is a bright future for Sunderland and ask ourselves instead what we need to do to offer people in Sunderland better prospects.”

The Conservatives were desperate to distance themselves from the report last night, which threatened to damage months of work by a team led by William Hague to win northern urban strongholds held by Labour and the Liberal Democrats.

Mr Cameron’s aides insisted that the timing of the report, as he begins a tour of eight marginal seats in the north of England, was a coincidence.

Chris Grayling, Shadow Minister for Liverpool, said: “This independent report does not reflect Conservative Party policy and we do not agree with its conclusions. We wholeheartedly support the regeneration of northern cities.”

Mr Cameron will start his tour today by visiting Carlisle, Westmoreland and Lonsdale and Barrow-in-Furness. He will then visit Morecambe and Lunesdale, Lancaster and Fleetwood, Southport, Warrington South and the Wirral tomorrow. He will also make an unannounced visit to Liverpool, one of the cities singled out by Policy Exchange. Aides insisted that this had always been part of the plan.

The report was released hours after Mr Cameron was asked whether the Conservatives were becoming complacent after a string of opinion polls had put them firmly in the lead.

The Tory leader refused to repeat a claim by Mr Hague that the Tories were now the “likely winners” of the next general election. He said that the party still had “a long way to go to really convince people that we are ready to run the country”.

He added: “There is not one ounce of complacency in me or my team. No smugness, no complacency, no triumphalism, never.”

The report by Policy Exchange, whose director recently went to head Boris Johnson’s policy team, says that many northern cities including Bolton and Oldham have “lost much of their raison d’être”. Following the decline of industry they had “little prospect of offering their residents the standard of living to which they aspire”.

Mass internal migration is the only answer to a decade of failed efforts to concentrate regeneration cash on other parts of the country, it says. Money being pumped into renewal projects and back-to-work schemes should be given directly to councils, according to local wage levels, to spend on regeneration measures.

The report concludes: “No one is suggesting that residents should be forced to move, but we do argue that they should be told the reality of the position: regeneration, in the sense of convergence, will not happen, because it is not possible.”

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• All that glitters is not sold in Wright’s world
• Believe it or not, Big Brother is your friend