SNP will embed in Westminster system to gain more power for Holyrood

As the third-largest party in the Commons, the SNP and its 56 MPs will for the first time have access to a little-known system of power known as "the usual channels".

It means the party will be granted two questions at Prime Minister's Questions every week, get seats on all Commons committees, and chair two of them.

The usual channels will also take the SNP into high-level meetings about parliamentary business with the Leader of the House and the Chief Whip.

In addition, the party's size increases its public funding, opening the taps on at least £1.2 million of so-called "short money" to cover back-office costs, which is calculated according to how many votes and seats an opposition

party wins.

A party source said that, rather than a guerilla-style opposition, the SNP group would be "fully engaged" with Westminster to extract maximum influence and put pressure on the government to adopt SNP measures.

The Sunday Herald also understands the SNP will seek help from other opposition parties to increase Holyrood's powers beyond those agreed in the all-party Smith Commission.

Senior Nationalists said they expected Labour and LibDem MPs to back further devolution in order to regain credibility after their collapse in Scotland.

Although the three parties could not force David Cameron's majority government to grant extra powers, they could claim to speak for 58 of Scotland's 59 MPs, and so paint the Tories as ignoring the wishes of the Scottish people.

One SNP MP said: "There was a series of reasons Scottish Labour fell on Thursday and one was the appearance of being anti-Scottish and forever saying no to reasonable demands that chimed with the public. You would have to be a pretty dim sort of Labour politician to keep saying 'No'."

On Friday, Cameron said that "as fast as I can", he would push forward draft legislation based on last year's Smith Commission on devolution, which was set up to deliver the pre-referendum "vow" of more powers.

Among the changes promised by the 44 clauses are the near-total devolution of income tax, a 50 per cent share of VAT receipts raised in Scotland, new borrowing powers and control of some benefits, including the power to top-up payments.

However, Nicola Sturgeon yesterday made it clear that was no longer enough, and she had told David Cameron as much after Thursday's result. She said: "He said to me his priority was implementing the Smith Commission proposals, and he would do that in good faith. I said to him I thought those proposals had to be looked at again because they weren't strong enough.

"Our manifesto was very clear. We said what's already on the table has to be implemented quickly, but that we don't think those proposals go far enough, and we said there were priority powers that we wanted to see devolved to Scotland - powers over business taxes, employment, minimum wage, welfare - because these are the levers we think are essential to get our economy growing, grow our revenues and lift people out of poverty. These will be discussions that I will certainly wish to have."

Scottish LibDem leader Willie Rennie accused the SNP of trying to undermine the Smith Commission.

"During the six-week General Election we never heard a peep from the SNP about the Smith Commission or the need to change it. They are redefining their mandate. They said a vote for the SNP was a vote for more public spending and against Trident. Apparently we weren't really listening and they really meant they would demand more powers."

Former SNP MP and deputy party leader Jim Sillars said Alex Salmond would prevent the new SNP intake getting too cosy at Westminster.

He said: "I've seen Westminster seduce people over the years. They did not seduce Alex Salmond. Alex Salmond is a very experienced operator in that particular arena. I know he keeps going back, but that's political necessity.

"He doesn't go back because he loves the place, and that's the important thing."