Next Conservative leader 'must look commit to the North East,' says Tory bigwig

Speaking to the Gazette’s sister title, the Yorkshire Post, Cabinet Secretary David Lidington, Theresa May's de facto deputy, said her successor must "reassert a continuing priority for the Northern Powerhouse".

He said: "I think this is important economically, but I think it is also important in terms of the cohesion of the country as a whole.

"If cities in the North of England feel that they are being left out and left behind then the country is going to feel more divided."

It came as more than 20 figures from industry and commerce wrote an open letter calling for the next Tory leader to back the HS2 rail project in its entirety.

There has been speculation that the next prime minister - the winner of the contest between Boris Johnson and Jeremy Hunt - could decide to axe the second phase of the project amid concerns over spiralling costs.

Mr Johnson has reportedly asked a former boss of the £56billion pound scheme to carry out a review if he is made PM, while Mr Hunt has said HS2 is "absolutely vital" and he would not scrap the project in its entirety.

Work is already under way on phase one, which will connect London and the West Midlands, although the full scheme would extend to Manchester, Leeds and Sheffield.

Mr Lidington said the next PM should give priority to the separet Northern Powerhouse Rail scheme to improve regional connectivity.