WENDY ALEXANDER WAS LAST NIGHT FORCED INTO A HUMILIATING CLIMBDOWN over her call last week for an early referendum on Scottish independence. Labour's Holyrood leader yesterday appeared to ditch her new-found support for an immediate referendum and backed away from supporting one. The U-turn points to prime minister Gordon Brown "having read the riot act" to Alexander and overruling her on the issue of a fast-tracked poll, opting for a barely credible show of unity rather than a split between Edinburgh and London.

But bitter briefing by both camps intensified, with Alexander aides calling Brown "a ditherer", while Brown's team dismissed Alexander as a "political pygmy". Brown also today signals a concentrated campaign to prevent the break-up of the UK through an alliance of pro-Union parties, business and trade unions. In an interview, he said he was personally "not persuaded" of the case for a referendum.

"I will do whatever is necessary to ensure the stability and maintenance of the Union," he said. "I will do anything and everything to ensure that the case for the Union, which has served Britain and the British people so well, is properly heard and advanced."

Alexander threw Labour into turmoil in both Scotland and England with her unexpected call for an immediate referendum, having previously said that a poll on independence was unnecessary.

She has said that the move was intended to expose the "hollowness" of the position of Alex Salmond's SNP administration, which has promised a referendum but not until 2010.

However, she has conspicuously failed to win the backing of ministers in Westminster, amid repeated claims that she omitted to consult Brown before issuing her call in a BBC Scotland television interview.

And yesterday she also faced calls from within the Scottish party for her resignation.

A senior Labour MSP said: "People are now talking about Wendy resigning. It's a question they are asking. Everyone is demoralised."

Another Labour MSP said: "Enough is enough. She has to go."

However, another friend of the embattled leader said of Brown: "A lot of people at Holyrood and at Westminster are not happy with him."

A second said: "The problem is Gordon's a ditherer."

A third source who is close to Alexander said of Brown's aides: "They just don't give a f*** about Scotland. All they care about is the next general election."

Former Labour first minister Henry McLeish also criticised Alexander. He said: "In one week we have managed to marginalise the Calman Commission, confuse the Scottish public, sour relations with the LibDems and Tories, and we now seem more keen than the SNP on a referendum."

Labour MSP George Foulkes, who supports the policy switch, said: "The mistake was the lack of timing and lack of consultation. If the timing had been right and the consultation extended, it could have been an inspired tactic."

SNP deputy leader Nicola Sturgeon said: "Words like laughing stock' do not even begin to reach the extent of Labour's disarray and humiliation.

"The abject humiliation of this climbdown statement leaves Wendy Alexander without a thread of credibility and her position as Labour leader now looks impossible."

A Scottish Labour executive meeting at Stirling yesterday confirmed that Alexander had moved away from her earlier bold claims.

In a statement, at no point does she back a referendum, a subject she only refers to in the past tense: "The SNP have now made clear they will block any Referendum Bill Labour might have introduced. Labour was aware of the Parliament's Standing Orders but we underestimated the SNP's desperation to use any device to avoid facing the verdict of the Scottish people. The SNP has therefore now blocked this route in the Scottish parliament."

She also attempted to repair relations with Brown by saying further decisions on constitutional change would come after the report of the Calman Commission, set up to review devolution, had been issued.

A spokesman for Alexander, asked if she still backed a referendum, told the Sunday Herald: "It depends. It's about scrutiny of the bill and it's about timing and process."

Asked if Alexander still stood by Duncan McNeil's statement, that Labour would not vote down any referendum bill, he said: "Duncan was talking about a referendum in principle, but that depends on the detail. You can't support any referendum."

On whether there was criticism of Alexander at the Stirling meeting, he said: "Nobody criticised her about exposing the SNP's hollowness. People will always quibble about timing."

No 10's assertion yesterday that Alexander was a "first rate leader" after a week in which one aide close to Brown called her a "political pygmy who had left the prime minister in a state of heated anger" looked praise too far and indicated that Alexander had been read the riot act.