The SNP will launch its General Election manifesto today, as it positions itself as a force for “progressive” change at Westminster.
The manifesto will present the party’s alternative to austerity, and is expected to contain proposals for real-terms spending increases of 0.5% a year.
It will also commit SNP MPs to participate in votes on major issues south of the border which have an impact on devolved areas in Scotland such as the NHS.
Opinion polls suggest the SNP could win as many as 56 of Scotland’s 59 seats at the election, and some members of the party believe it has proved its “complete relevance” to a Westminster election for the first time.
Nicola Sturgeon insisted the party would not be a disruptive force in the House of Commons, stating that SNP MPs can build alliances with anti-Tory MPs in Westminster on many issues, such as the NHS.
Speaking ahead of the manifesto launch in Edinburgh, the SNP leader said: “The NHS is so vitally precious to us all – and we rely on it to be there for us when we need it.
“In government, the SNP has shown wholehearted commitment to protecting and improving Scotland’s NHS – and we have made clear that we are prepared to support a Bill at Westminster to restore the National Health Service in England.
“We can end the Tory agenda of cuts, privatisation and patient charging … threatening the future of the NHS south of the border, which will also protect Scotland’s budget and NHS.
“Over the past five years, we have protected Scottish NHS spending from Westminster austerity. A strong team of SNP MPs in a hung parliament at Westminster can go further, proposing increases in health spending across the UK.”
Ms Sturgeon has already offered to work informally with a Labour government to lock David Cameron out of Downing Street.
Ed Miliband has rejected the SNP offer, but Scottish Conservative leader Ruth Davidson will warn today that Labour are preparing to do a “back-room deal” with the nationalists.
Ms Sturgeon has refused to rule out a second independence referendum, with the Tories arguing the union could be under threat again.
Giving a keynote speech in Glasgow, Ms Davidson will say: “Surely it’s time that Labour woke up and realised that the SNP’s first and last priority will always be separation.”
“If Nicola Sturgeon really wants to prove her constructive credentials, there’s a test she has to meet.
“It’s to accept – right now, before the election – that the United Kingdom is staying together for the next generation, in line with her own pledge, and in line with the decision made by the people of Scotland last year.”
Mr Miliband, who will deliver a speech to the Scottish Trades Union Congress today, said: “Nicola Sturgeon is asking people to gamble on getting rid of a Tory government – the only way to guarantee getting rid of a Tory government is to vote Labour.”
Scottish Labour leader Jim Murphy wants to know if the SNP manifesto will include a commitment to push for full fiscal autonomy and detail the figures behind it.
He said the SNP manifesto will “fail the test of credibility unless it’s honest about the devastating impact of full fiscal autonomy”.
Mr Murphy will take to the football pitch in Edinburgh today for a charity penalty shoot-out against the Conservatives organised by a motor neurone disease campaigner calling for more research funding.
Speaking before the event, Mr Murphy said: “A Labour Government will give disabled people in Scotland a say in the decisions that affect their everyday lives.
“The alternative facing Scots in this election is more austerity. The Tories will impose another five years of brutal cuts and the SNP’s plan for full fiscal autonomy would mean extra austerity that would hit the most vulnerable Scots the worst.”
Meanwhile, Liberal Democrat Scottish Secretary Alistair Carmichael has challenged the SNP to remove a “threat to small businesses in Scotland” caused by the prospect of a second referendum.
Mr Carmichael set out Liberal Democrat manifesto proposals to expand the work of the British Business Bank.
He said: “What companies will want to hear from the SNP is a cast-iron guarantee that they will support the work of the British Business Bank. Projects and funding deals must not be put at risk by the SNP’s plan for a second referendum.
“Anything called ‘British’ will have a question mark over its future in a second referendum. The SNP need to provide guarantees that they will leave it alone and let it get on with its work.”