Tony Blair has ordered his Cabinet colleagues to clear their diaries and spend time in Scotland over the last ten days of the election campaign in a desperate attempt to turn the tide on the Nationalists.

Although the opinion polls are still refusing to offer much comfort for Labour, the Prime Minister has decided that Scotland is now the key battle-ground of the local elections on May 3 and that the SNP can be overtaken even at this stage.

The Prime Minister’s strategy, however, risks the danger of leaving his party in Scotland open to opposition charges that it is having to sideline Jack McConnell, the First Minister.

The Prime Minister believes that the SNP decision late last week not to publish any document outlining the economic case for independence has given Labour a key opening to claim that the Nationalists are incapable of answering vital questions.

A key Downing Street source told The Times: “We want the question of why Labour is behind in the polls to change to one about why the SNP is refusing to answer questions about their economic policies and their core policy. We believe that when that question is asked, the polls will start to go our way.”David Miliband, the Environment Secretary, was on the campaign trail in Glasgow yesterday and he will be followed by Gordon Brown today.

Downing Street says that Mr Blair wants to plant the message in voters’ minds that, while they may consider voting SNP because they “fancy a change”, that cannot be viewed as a safe vote because of the SNP’s independence aim. He will make the case that there is “something fundamentally wrong” when the independence cause can draw support both from right-wing businessmen who believe in an unfettered free market and from anticapitalist campaigners such as Tommy Sheridan.

The scale of Mr Blair’s task in aiming to stop the SNP momentum was underlined yesterday when two more polls in Scotland gave the Nationalists a clear lead. They followed a poll by Populus for The Times on Friday which also showed that Labour was making only small inroads into the SNP lead in the race for power at Holyrood.

However, Mr Blair has been told by Lord Gould, his personal polling guru, that the final ten days of the campaign will be decisive and that the large number of undecided Scottish voters means that there is all still to play for.

David Cameron, the Conservative leader, dismissed poll findings suggesting that his party is going nowhere in the Scottish election campaign. A YouGov poll for The Sunday Times put the Tories at 14 per cent in the constituency vote and 13 per cent in the regional list vote, equating to 16 seats, while a Scottish Opinion survey for The Mail on Sunday put them on 10 per cent and 11 per cent, equating to 13 seats.

Mr Cameron told The Politics Showon BBC One: “The argument in Scotland that I’m making is look, you had a Labour Government in Scotland. If you don’t want the divorce offered by the SNP, the Conservative party is now a sensible, centre-right party.”

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