A report by Sheffield academics seen by The Yorkshire Post says the Government's current policies to tackle regional inequalities "offer funding that mostly isn’t new, is often short-term, and looks likely to be scattered widely across the country".
The Plan for the North report by Steve Fothergill and Tony Gore of Sheffield Hallam University calls for a host of new measures including a substantial diversion of government R&D spending to the North and extra funding to make areas with low land values more attractive to private investors.
The document was commissioned by South Yorkshire metro mayor Dan Jarvis as well as Ros Jones and Steve Houghton, the leaders of Doncaster and Barnsley councils.
And in a letter to the PM, signed by 43 other political leaders across northern England "that the practical steps towards levelling up the North have so far been limited and disappointing".
In a message to the Westminster government, the three Labour leaders in South Yorkshire said: "That levelling up is now firmly on the agenda is a big step forward but there is still a huge gulf between your aspirations and the delivery of practical policies that will make a difference.
"We don’t need schemes that are dreamt up in Whitehall by officials with scant understanding of the North and even less knowledge of the long history of policies to help less prosperous part of the country, of what works and what doesn’t.
"We also don’t need still more competitive bidding that sets authority against authority, with no certainty of outcome, and erodes the collaborative cross-border working that so often proves most effective."
It came as Boris Johnson visited Batley and Spen yesterday to campaign for the Tory candidate in the upcoming by-election, which Conservatives hope to win and pile more pressure on Labour leader Keir Starmer.
But the Tories were also reeling yesterday after being beaten by the Liberal Democrat in a by-election Chesham and Amersham, which had been a Conservative stronghold since its creation in 1974.
The result cast doubt on whether the party can hold onto seats in the so-called 'blue wall' in the South East.
Meanwhile, writing in The Yorkshire Post today, Rotherham-born former Education Secretary says Keir Starmer and the current Labour leadership "have failed to show any meaningful engagement with today’s politics of aspiration, the ‘levelling up’ agenda."
In response, a Government spokesman said: “We are totally committed to spreading opportunity and investment across the whole of the UK, which is why we’re investing £100 billion in capital investment this year, as well as creating the £4.8 billion Levelling Up Fund and launching the new UK Infrastructure Bank in Leeds.
“Thirty-three communities in the north have now received £ 812 million from our Towns Fund and several northern towns have been selected as the location for new Freeports to help them become national hubs for international trade and local regeneration.”
Outlining the measures they would like to see to strengthen the North's economy, the authors call for a new emphasis on growing the manufacturing sector, "which remains a large component of the North’s economy."
They add: There needs to be a business environment that encourages investment, a competitive exchange rate, a budget strategy that sustains demand, and protection from unfair foreign competition.
And they recommend investment in the green economy to lower carbon emissions and bring new jobs to the North, adding: "Energy intensive industries, which are important in parts of the North, should be helped to reduce their carbon emissions, not discarded."