Labour leader Ed Miliband has formally ruled out a post-election coalition with the SNP.
“Labour will not go into coalition with the SNP. There will not be any SNP ministers in any government I lead," he told an event in Leeds.
Until today, Labour ministers have failed to explicitly rule out a coalition with Nicola Sturgeon’s party.
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Miliband also claimed the Conservatives had abandoned any pretence of representing people in Scotland, saying:
"This whole episode also proves something else: the Conservative party has given up on the Scottish people; it’s a Conservative party that now simply wants to use Scotland as a political device, a Conservative party that doesn’t even try to pretend that they can represent the whole country, a Conservative party that is now a real threat to the integrity of the United Kingdom.”
The Labour leader sought to reframe the arguments over coalition by focusing on the possibility of a Conservative-Ukip pact.
"The real danger to the country is a Tory government propped up by Ukip – that is the real threat to working families," he argued.
SNP leader Nicola Sturgeon said she was not surprised at Mr Miliband’s announcement, since she had been saying for weeks that a formal SNP-Labour coalition was highly unlikely.
She told Sky News: “Nothing Ed Miliband has said today has changed that for me. I still point to the reality that if there are more anti-Tory MPs in the House of Commons than Tory MPs... we can work together to keep the Tories out of government, which is what most people in Scotland want to see.”
The Conservatives issued a swift response to the announcement, claiming that Labour could still do a deal with the SNP involving support on individual votes.
"This changes nothing. Ed Miliband will not rule out a deal with the SNP because he knows it's impossible to become prime minister without being carried into Downing Street in Alex Salmond's pocket," a Tory spokesman said.
"There have been over 1,200 votes in this Parliament. Vote by vote, bill by bill, issue by issue, Ed Miliband would have to do a deal with the SNP on each and every one of them."