A CONCERTED Whitehall campaign designed to pressurise the Scottish Government has resulted in a war of words breaking out between the Liberal Democrats and the SNP, with Danny Alexander branding First Minister Alex Salmond and his colleagues "enemies of growth".

In his keynote speech to the LibDem conference, the Chief Secretary to the Treasury told delegates he would “name and shame” those standing in the way of “the central national purpose” of creating growth -- and then duly named the Scottish Nationalists.

He said: “We’ll never let the anti-European isolationists or nationalists frustrate our national interest. They are the enemies of growth”.

Last night, John Swinney hit back, saying: “Danny Alexander must be living in a parallel universe. The reality is the exact opposite of his silly jibe -- the SNP government are building recovery in Scotland, and it is the Tory-LibDem Coalition which is smothering economic growth.

“The SNP government are delivering a ‘plan MacB’, which is cutting unemployment in Scotland while it rises in every other part of the UK, and it is vital that the Tory-LibDem Coalition at Westminster follows the Scottish lead -- otherwise there is a real risk that they will derail our recovery,” added the Scottish Finance Secretary.

The broadside follows an even stronger put-down by Deputy Chief Whip Alistair Carmichael at a conference rally on Saturday, when he scoffed at a threat by Mr Swinney to veto the Scotland Bill.

Last week, the Scottish Finance Secretary reacted with disbelief when Michael Moore, the Scottish Secretary, appearing before a Holyrood committee, revealed the UK Government had not yet worked out by how much the annual Scottish block grant would be cut when the Scottish income tax comes in to being in 2016.

Mr Swinney said: “Mr Moore cannot possibly expect the Scottish Parliament to sign the blank cheque he admitted to at the committee meeting.”

The Scotland Bill, which will give the Scottish Parliament extra financial powers, will only be passed with Holyrood’s consent.

Mr Carmichael, the MP for Orkney and Shetland, said Mr Swinney’s threat of a veto beggared belief, given a sizeable tranche of power was being handed over to Edinburgh.

He told delegates: “These are not the actions of a Scottish Nationalist government, these are the actions of a Scottish national embarrassment.”

The Herald has been told considerably more pressure will be put on the SNP Government by Whitehall on policy detail in the coming months.

Already, ministers have given co-ordinated speeches and earlier this month David Gauke, the Treasury Minister, rubbished Mr Swinney’s proposal for the devolution of corporation tax.

A senior Whitehall source said: “From now on we are going to be more pro-active -- not just on constitutional issues but across the whole waterfront of policy. We have to put the SNP more on the spot.”

Mr Salmond launched his own attack against Mr Alexander and the Coalition, accusing them of panicking in the face of being the “Tory frontman” for the UK Government’s cuts agenda.

Meanwhile, the prospect of a swift cut in the 50p tax rate disappeared from view yesterday as a series of LibDem ministers ruled it out. Nick Clegg acknowledged the possibility of replacing the tax but made clear this would not happen any time soon.

It would only be considered after the burden on the poorest was reduced further; the aim is to raise the tax-free personal allowance to £10,000 by 2015.

The Deputy Prime Minister insisted: “I don’t think it is morally or even economically right to unilaterally lower the tax burden on the very, very wealthiest when we haven’t made much progress, as we wanted to, on lowering taxes for low incomes.”

Meantime, in his speech to conference Mr Alexander made much of a crackdown on tax avoidance and evasion with the recruitment of an additional 2250 staff at HMRC.

The Chief Secretary told delegates the crackdown was already “bearing fruit”, raising an extra £2 billion this year with the aim of raising an extra £7bn by 2015. The so-called “affluent team” will target the 350,000 wealthiest taxpayers.