Alex Salmond suggested that jettisoning an attempt by the Conservatives to govern alone would allow the SNP to prop up a minority Labour administration . Alex Salmond has threatened to bring down a Conservative minority government, even if David Cameron wins more seats than Ed Miliband. The former Scottish First Minister said the Scottish National Party would vote down a Tory Queen's Speech if it holds the balance of power after the general election. Latest polls suggest the SNP will gain dozens of seats in Scotland, depriving Labour of a majority and able to call the shots in Westminster. Mr Salmond suggested that jettisoning an attempt by the Conservatives to govern alone would allow the SNP to prop up a minority Labour administration. The Tories said it was proof the SNP would 'sabotage the democratic will of the British people' to install Mr Miliband in Downing Street. Speaking to the New Statesman magazine, Mr Salmond said the SNP could enter a 'confidence and supply' arrangement with Labour - under which the smaller party would agree not to bring down a minority government in return for concessions on particular priorities. But he said it was more probable that it would offer its support on a vote-by-vote basis and would make amendments to any budget put forward by Ed Balls to introduce 'progressive tax measures'. With opinion polls suggesting the SNP are headed for dozens of gains from Labour and the Liberal Democrats north of the border, Mr Salmond - who is standing in the Gordon seat being vacated by veteran Lib Dem Sir Malcolm Bruce - would say only that he expects the party to win 'a barrel-load' of seats at Westminster. He predicted that Lib Dems would not be 'a big factor' in negotiations on forming the new government, as 'if the Liberals are reduced to half their MPs the last thing they're going to be doing is going into a coalition'. 'The surviving half will want to survive,' he said. This would mean the SNP, unionist parties from Northern Ireland and other smaller parties would be crucial to the outcome. Mr Salmond rejected Labour's argument that the party with the most seats after the May 7 poll will have the opportunity to form the government, insisting that the key question is which leader can command a majority in the Commons. 'The Tories would have to go straight effectively for a vote of confidence - usually the Queen's Speech, although it could be otherwise, of course, and we'd be voting against,' said Mr Salmond. 'So if Labour joins us in that pledge, then that's Cameron locked out. And then under the (Fixed-Term) Parliaments Act that the Westminster parliament's passed but nobody seems to have read, you'd then have a two-week period to form another government - and of course you want to form another government because this might be people's only chance to form another government.' The SNP would act to prop up a Labour government with Ed Miliband in Number 10, even if David Cameron wins more seats . Although Mr Cameron would remain incumbent Prime Minister until a new government was formed, the Act - passed by the coalition in 2011 - would restrict his ability to call a new election in the hope of securing a decisive result, said Mr Salmond. The former SNP leader said he had 'no idea' whether a Labour government emerging from such a process would have Mr Miliband as its leader, and suggested that he was wrong to have ruled out formal coalition with the SNP so firmly . 'If I were him, I wouldn't have ruled it out,' said Mr Salmond. 'Nicola (Sturgeon, the SNP leader) has always said that she thought full coalition was unlikely. But she didn't rule it out: she said it was highly unlikely ... It's still highly unlikely.' Asked what he saw as the probable outcome, Mr Salmond said: 'I think probable would be vote-by-vote (support for Labour), and possible would be confidence and supply.' A new poll of voters in Scotland this week put Labour down to just 27 per cent, which Professor John Curtice says could leave the party with just two MPs, the same number as the Tories . Mr Salmond said it was 'bad politics' for Mr Cameron to float the prospect of English votes for English laws on the morning after last year's independence referendum and said it was now 'not a question of if, but when' a second referendum on separation from the rest of the UK would take place. A Conservative spokesman said: 'Alex Salmond has confirmed he would sabotage the democratic will of the British people in order to make Ed Miliband prime minister. 'That would mean chaos for Britain, with weak Ed Miliband dancing to Alex Salmond's tune. The only way to protect Trident, keep Britain together and safeguard the economy is to vote Conservative.'
Ex-SNP leader says he would lead revolt against a Tory Queen's Speech . Cameron would have first shot at forming a government after the election . But if legislation is rejected in the Commons Labour would have a chance . Salmond suggests SNP would not opt for full-blown coalition with Labour . Tories say he would 'sabotage the democratic will of the British people'