Wendy Alexander yesterday confirmed the rift that has opened up with Gordon Brown over her support for an independence referendum.

A day after the Prime Minister and Labour leader said she was not in favour of such a vote now, she told MSPs that she is, and urged First Minister Alex Salmond to bring forward a referendum bill as soon as next week.

Ms Alexander, Labour's leader at Holyrood, who has faced a tumultuous week of confusion over her sudden U-turn on supporting the referendum last Sunday, raised the issue during First Minister's question time at Holyrood - as did Tory leader Annabel Goldie and LibDem Nicol Stephen.

Ms Alexander was mocked when she said: "I am not the problem, Labour is not the problem," going on to argue: "The First Minister is the problem when it comes to resolving these issues in the national interest."

Mr Salmond replied he will stick to the SNP's manifesto plan to hold a referendum in 2010, adding: "While I would not say Wendy Alexander is the only problem the Labour party has, I think quite convincingly after the last few days that she is not the answer."

Ms Alexander had opened her questions saying: "The First Minister has been a Nationalist all his political life. I'm giving him the opportunity to resolve the issue. Why won't he take it?"

She said she wants Scotland to have a choice sooner rather than later, and cited Mr Salmond's claim that 80% of Scots want a referendum: "So why are we still waiting?"

She argued the uncertainty is damaging to Scotland, referring to the CBI Scotland director saying it was time to "lance this boil".

Ms Alexander said the SNP wants to delay so that it can "foment grievance, fray the relationship, and because they fear the result".

Mr Salmond welcomed Labour's support for the use of a referendum to decide Scotland's constitutional future, and said he looked forward to the support of Labour when he tables a bill in two years.

"Given the progress that Wendy Alexander has made in the last few days, who knows what side she'll be campaigning on?" he taunted.

Ms Alexander said it was too serious an issue for humour, to which Mr Salmond replied he agrees it is serious: "But it is impossible for anyone outside the Labour Party - and I think most people in it - to take the Labour Party seriously after the last few days."

Scottish Tory leader Annabel Goldie said Labour had become the SNP's "greatest ally in breaking up Britain", arguing that while Labour "may have abandoned" supporters of devolution, Tories have not.