THE UK's welfare chief is to volunteer to be grilled by MSPs as part of a new drive to end "bickering and blame games" between Westminster and Holyrood.

Stephen Crabb, Secretary of State for Work and Pensions, is to take a different approach to predecessor Iain Duncan Smith, who was criticised for snubbing requests to appear before the Scottish Parliament's welfare reform committee to be questioned about highly contentious overhauls to the benefits system.

Stephen Crabb, Secretary of State for Work and Pensions, will appear before MSPs at Holyrood

David Mundell, the Scottish Secretary, revealed that Mr Crabb would be happy to make the trip north in a speech this morning, in which he said the public was sick of spats between Governments in London and Edinburgh and called for a more constructive working relationship between the two administrations.

Mr Mundell said: "What I can confirm is that Stephen Crabb will offer to appear before the successor to the welfare reform committee, he is very keen to engage in a dialogue with the Scottish Parliament and is very keen to be available and accessible in Scotland.

"I think it's very important that we have that dialogue not only from our Government's perspective, to set out our position on a range of issues, but during this period of very significant change, that there is as close working as possible with the Scottish Government and parliament."

Mr Mundell said that Holyrood was set to become responsible for a significant raft of new welfare powers, worth around £2.7 billion a year, and would be able to offer top-up payments to tax credits, universal credit and child benefit.

It will also gain responsibility for carer's allowance, disability payments, winter fuel allowances, maternity payments and funeral benefits. The Scottish Government will be able to create new benefits in any area of devolved responsibility.

In its manifesto, the SNP described the welfare powers being devolved as "limited" but promised to increase carer's allowance, restore housing benefit to 18 to 21 year-olds and reform assessment procedures for disability payments, building a system with "fairness, respect and dignity at its heart."

On the ability to create new benefits, Mr Mundell said: "I look forward to hearing from the Scottish Government how they intend to use that power, which they fought so hard to ensure they had."

However, he said that a new era of co-operation would not extend to allowing the Scottish Government to call another independence referendum at the time of its choosing, saying it had no mandate to do so, and also played down suggestions that the Tories becoming the main opposition at Holyrood would lead to an increase in tensions between Edinburgh and London.

He added: "It's not Nicola Sturgeon's choice as to whether there will be a second independence referendum. My position is quite clear, the Prime Minister's position is quite clear. There is no mandate for a second referendum in the SNP manifesto, and indeed, the votes many people cast in the election were votes to ensure the SNP Government did not have a majority and were not in a position to seek to take forward a second referendum.

"If the First Minister is listening to the people of Scotland, then she will stop talking about a second referendum and get on with governing Scotland."

The Scottish Secretary also suggested the UK Government was still not prepared to offer Scotland an opt-out from the Trade Union Bill, which will impose new restrictions on workers' rights and is vehemently opposed by both the SNP and Labour.

He said: "The Scottish Parliament itself was very clear that the areas covered by the Trade Union Bill were reserved matters and therefore matters for which the UK Government and UK Parliament were to make the decisions, but obviously, these matters always continue to have potential for ongoing dialogue."

Responding to Mr Mundell's comments about a second referendum, a spokesman for the SNP said that as Scotland's only Tory MP, he was "just about the last person who should be lecturing others on a democratic mandate."

He added: "When it comes to Scotland's future, we have already said that there will not be another independence referendum without a material change in circumstances - such as being taken out of Europe against our will - or clear and sustained evidence that independence has become the majority view of people across Scotland.

"That remains the case and the election result has changed nothing in that respect.

"Parliament retains a majority of MSPs from parties which backed independence in the 2014 referendum and any proposal for a second referendum in this term would be a matter for parliament has a whole to consider and vote on.

"But it is the people of Scotland who are sovereign, and ultimately it will be they and only they who decide this country's future."