Former Finance Minister Tom McCabe said the next Labour leader at Holyrood should have total power over Scottish affairs, claiming Jack McConnell had been hamstrung by Westminster MPs while in office.

Andy Kerr, the bookies' favourite to win the Scottish Labour leadership race, said he wanted the job to be "beefed up". His allies are demanding the new leader should be seen as "top dog" in Scotland, ahead of Des Browne, the Scottish Secretary in the UK Government.

But the moves prompted a backlash from several MPs, who insisted that Scottish Labour had to remain part of the UK-wide party in order to take on the Nationalists. They warned the move was part of an attempt to create an "SNP Mark Two".

Among those opposing Kerr is his own Labour MP at Westminster, Adam Ingram, with whom he shares an office in East Kilbride. Ingram said he will not be backing his own MSP for the top job and, in a further riposte to Kerr, has insisted that the vacant post is "for the leader of MSPs at Holyrood, not for the leader in Scotland".

The vacancy was triggered after the resignation of Wendy Alexander, who took over from Jack McConnell this time last year. The leader's job is routinely referred to as the top post in Scotland, but, in fact, the leader of the Scottish party is the UK leader, Gordon Brown. MSPs around Kerr insist that the new Holyrood leader should be in charge in Scotland.

Scotland on Sunday understands that Kerr's call for a stronger leadership role is being backed by both McConnell and Alexander, who have complained in the past that their own time in office was "hampered" by the influence of the UK party.

McCabe said that the Holyrood leader should be in "complete control" of the organisation and the policies affecting Scotland.

McCabe told Scotland on Sunday that there were some in the party who were "still in denial" following last year's election defeat to the SNP, and their catastrophic loss in the Glasgow East by-election two weeks ago.

He said both MPs and Labour councillors now have to accept that Holyrood needs to take priority in Scotland.

"We need to learn the lessons from the SNP," he said. "They are able to state their case while the Scottish Labour leader has to be more guarded. People in Westminster and local Government need to realise the realities of devolution. That hasn't happened."

He said the loss of Glasgow East had been a further example of the SNP showing they were able to win over Labour supporters.

Compared with the SNP leader at Holyrood – who is in charge of the entire party – McCabe added: "What I would say is that as things currently stand, they (the Holyrood leader] leave themselves at a severe disadvantage."

However, the call for the Holyrood leader to be elevated in importance was met with immediate opposition from elsewhere in the party.

Ingram told his local news paper: "Let's not forget this vote is for the leader of MSPs at Holyrood, not for the leader in Scotland." Another MP said: "Everyone talks about Labour MPs being London-centric. Nobody talks about the MSPs being Edinburgh-centric, but that is what they are. This is basically about creating an SNP Mark Two."

A third Scottish MP said: "It is madness to say that they have to have a dividing line with London Labour. This kind of thing drove Henry (McLeish] and it drove Jack and it has got us precisely nowhere. We need someone to change the record."

Kerr attempted to play down his call for more power after launching his leadership bid last week, insisting he did not want to rip up the party's rule book. However, allies say that he will enact major changes to the status of the job if elected.

They claim that when in power McConnell had to "phone up Gordon Brown" when he wanted to enact policies, in order to check they would be acceptable. "That can't go on any more," said one of Kerr's team.

But Westminster sources say the move could trigger a major turf war if, as expected, Brown decides in his forthcoming reshuffle to create a more powerful Scottish Secretary. MPs believe Brown may boost the role – currently undertaken by Defence Secretary Browne – as he seeks to take on the SNP.

The other two candidates for the job, Iain Gray and Cathy Jamieson, have adopted a more cautious approach to the status of the job so far.

A spokesman for Gray said: "His position is that it doesn't matter about the name of the job, the person who wins this contest will have a mandate.

"That is what you are going to get from going to the entire Electoral College. The Scottish Labour leader at Holyrood will be a distinctive Scottish voice."

Kerr says today that £150m of Lottery money should be transferred to Scotland as a legacy payment following Glasgow's Commonwealth Games in 2014.

SNP MP Angus Robertson said: "This is a classic turf war. Labour politicians in both parliaments are so preoccupied with having power they are rapidly losing it."

Big guns rally to defend Brown

THREE Labour heavyweights have issued a public vote of confidence in Gordon Brown in a bid to crush speculation of a leadership bid this autumn.

Chancellor Alistair Darling, deputy leader Harriet Harman and skills secretary John Denham all spoke out, insisting that Brown was the best person to lead the party.

They were forced to act after David Miliband last week laid out his own vision for Labour's future in a newspaper article which omitted to mention the Prime Minister once.

Labour sources supportive of Miliband continue to insist that a change is required at the top if the party is to avoid plummeting to an electoral disaster against the resurgent Tories.

But, in what is a coordinated attempt to counter the speculation, Brown's Cabinet is now hitting back.

"The determination and strong purpose shown by Gordon are why he will lead us into the next election and win the confidence of the country. All of us are focused on that," Darling said.

Harman added: "When you face these kinds of global problems, you need as Prime Minister someone who is respected on the international stage and someone whose hard work and ability over the last 11 years has made Britain better off."

And in a coded warning to Miliband and his allies, Denham warned: "We do not want a summer of leadership speculation. We have got a good case to make and we should get out there and make it. All of this leadership speculation gets in the way of us putting our message across."

The intervention is part of a major counteroffensive by Brown and Labour's whips following the week's events. Although Labour MPs are usually banned by party whips from taking part in any surveys carried out by media organisations, they have been told that they should reply on any about the Prime Minister to express loyalty to Brown.

The counteroffensives also saw The Apprentice star Sir Alan Sugar coming out to back Brown yesterday in a newspaper article.

Writing in the Sun, he said: "We will make a fatal error by not giving Gordon a chance to roll out his plans. Yes, he is a serious bloke. Dare I say he may come over a bit boring – he's not a trained actor, he's a deep thinker. Let me tell you, this fellow is no mug."

Brown is still on holiday but is expected to begin a major attempt to reassert his authority by the end of this month. A reshuffle is widely expected, along with an economic recovery plan, with tax cuts expected.

Chancellor Alistair Darling may borrow more funds in order to pay for tax cuts on fuel, stamp duty and income, although Treasury sources are now playing down chances of a one-off windfall tax on energy companies.

Nevertheless, First Minister Alex Salmond will today add more pressure on the Prime Minister by insisting that there is a strong case for such a windfall tax. He also says the Treasury should break its own rules on borrowing and go further into the red in order to help ease the pain for taxpayers.

In a warning to the Prime Minister, Salmond will say that cuts in fuel duty and reductions in heating costs are necessary to restore consumer confidence.

Salmond says that in the last downturn in the early 1990s the UK Government borrowed far more as it sought to pump up the economy. He says that Brown and Darling should now do the same.

"In moral terms, Government cannot stand aside and watch families being driven into fuel poverty," he said.

And he added: "I urge the Prime Minister to come out of his bunker and tackle the deflationary forces in the economy. Action must be taken to resurrect consumer confidence."

Salmond will call for specific measures in Scotland, including a demand for the Treasury to allocate a share of its North Sea oil revenues.

One of the contenders for the vacant Holyrood Labour leader post, Cathy Jamieson, hit out at Salmond last night over what she described as his "megaphone diplomacy".