Ed Miliband will today tell Scottish voters not to use their referendum to rid themselves of the Tory-led government... because he says he’ll win the general election.

The Labour leader will claim the Conservatives are ‘on their way out’ in an attempt to persuade his party’s traditional voters to reject independence.

The latest opinion polls show up to 30 per cent of Labour’s natural supporters may be ready to switch allegiance and back Alex Salmond’s plan to break up Britain.

Pledge: Pro-union campaigners Ed Miliband and wife Justine. The Labour leader will today make a series of pledges to shore up support for the Scottish No vote

Many are thought to have been wooed by the SNP’s message that a vote for independence would mean Scotland would no longer be ruled by English Tory ministers sitting in Westminster.

Now, in a speech at Blantyre in South Lanarkshire, Mr Miliband will make a series of pledges in a bid to shore up the No vote.

The tone of the speech is in marked contrast to the pro-union campaign so far, which has seen the Conservatives, Labour and Liberal Democrats working closely together. It is understood the new tactic was signed off by Tory strategists within the Better Together campaign.

Winning over undecided Scots in Labour heartlands such as Glasgow is seen as crucial to reviving the No campaign, which has seen its lead slip from 22 percentage points to just six in one month.

Mr Miliband will say that ‘as Prime Minister’ in eight months’ time he will tax bankers’ bonuses, raise the minimum wage, introduce a new higher rate of tax and abolish the so-called bedroom tax.

‘The SNP want to tell you we can’t defeat the Tories. They are wrong,’ he will say. ‘Change is coming in the UK – the Tories are on their way out. They are losing their MPs, they are defecting, divided and downhearted. A Labour government is within our grasp. With that election in just eight months’ time the change Scotland needs is on its way. Electing a Labour government is the way to change Scotland.’

Poll shock: Alex Salmond, pictured with Yes-branded cakes, has seen his side rocket to 47 per cent of the vote

He will claim: ‘We will abolish the bedroom tax. Abolish it in Dundee, in Glasgow, but also in Carlisle, Newcastle and Nottingham.’

The attack on the Tories comes after the leader of the Scottish Conservatives played down her party’s chances at the next election.

During a TV debate on Tuesday, Ruth Davidson said: ‘Frankly [a Conservative victory in May] isn’t looking likely by the polls, but we are trying our best.’ The comments were read as an attempt to persuade Scots to stay in the UK.

Mr Miliband, David Cameron and Nick Clegg were accused of complacency at Prime Minister’s Questions yesterday, as the main parties were urged to ‘drop everything’ and fight for a No vote.

Tory MP Sir Edward Leigh said: ‘If we were to lose the Union, it would be not only a disaster for Scotland, but a national humiliation of catastrophic proportions.

‘I say gently to the three party leaders that perhaps we have been a bit complacent up to now. I urge them, over the next two weeks, to drop everything else and stand shoulder to shoulder to fight for the Union that we love and believe in.’

Mr Cameron replied: ‘The leaders of the parties in this House have all put aside their differences and said that, in spite of the political differences we have, we all agree about one thing: not only is Scotland better off inside the United Kingdom, but the United Kingdom is better off with Scotland inside it.’

Of the 650 MPs in Westminster, 59 represent Scottish seats; Labour, which accounts for 41 of these, would be the hardest-hit by a Yes vote. Without Scotland, the Tories would have had a 21-seat majority at the 2010 election. Labour still would have won majorities in 1997, 2001 and 2005.

The Scottish Nationalists’ campaign has been boosted by two polls in the last week, which both suggested 47 per cent of decided voters will back independence, compared with 53 per cent who will vote No. Mr Salmond’s former policy chief yesterday claimed that SNP insiders now believe they can win the referendum by snaring 55 per cent of the voters.

Both sides in the independence battle are stepping up pressure in the central belt, dominated by Labour MPs, as shown in this map of the 2010 general election result

This could lead the UK into a eurozone-style crisis, Goldman Sachs has warned. Its analysts said Scottish independence was still unlikely, but ‘could have severe consequences’ for the UK and Scottish economies.

‘The most important specific risk, in our view, is that the uncertainty over whether an independent Scotland would be able to retain sterling as its currency could result in a [Europe-style] currency crisis occurring within the UK,’ wrote Kevin Daly, a senior economist at the bank.

He also warned that an independent Scotland would face much higher borrowing costs, and be forced to cut public services.