The Labour party put on a show of closing ranks behind Gordon Brown today as it opened its annual conference in Manchester.

The Prime Minister received cheers and a 32-second standing ovation as he came onto the stage at the start of the conference.

Already boosted by a public declaration of support from Foreign Secretary David Miliband, the man seen as most likely to challenge him, and a £1m donation from the Harry Potter author JK Rowling, Mr Brown heard several speakers demand party unity.

Ed Milliband, the Cabinet Office Minister and brother of the Foreign Secretary, himself received a standing ovation from parts of the conference as he said the party had a duty to support the Prime Minister.

Mr Brown responded by promising to do “whatever it takes” to clean up the financial system and protect British jobs and savings. He acknowledged he was going through “testing times”, but insisted he was determined to continue to serve all the people of the country.

He sought to brush off speculation about a possible challenge to his leadership, telling delegates he did not want to talk about “that other stuff”.

And he promised to seek the return of £8 million transferred from Lehman Brothers offices in London to the USA shortly before the bank’s collapse last weekend, in order to ensure that workers including low-paid cleaners and computer operators get their wages.

Mr Brown received a generally warm response from activists, who appeared to have decided to put thoughts of rebellion on ice at least for the five days of the Manchester gathering.

In a question and answer session dominated by the economy, Mr Brown made only one veiled reference to the debate over his leadership which has seen a minister resign and three other Labour MPs leave government posts.

“What a week. I don’t think I’ve ever seen anything like it,” he said. “Not that other stuff, but a world economy changing almost by the day and almost by the hour.”

In an apparent admission of the superior presentation skills of David Cameron, the Conservative leader, he told delegates: “At testing times like these, this is not about public relations and slogans and whether you have got the right language. The real test is of your judgment. The real test is of the choices you make.”

While Conservatives would have allowed Northern Rock to fail and would not have taken action to stop short-selling of financial stocks, the Government took “the right decision” to protect jobs and savings and deliver a better financial system, he said.

Mr Brown said “global problems need global solutions” and confirmed he would be going to the US immediately after the conference to talk to financial institutions and governments about the crisis.

He told delegates: “When people ask what we will do to sort out the financial system and ensure there is responsibility and not irresponsibility, I tell you in three words: whatever it takes."

Earlier Ed Miliband praised Mr Brown’s “resolve, toughness and deep sense of fairness”.

He said: “We meet here in tough times for our country and tough times for our party too. But all of us know our responsibility as we’ve watched in the last week the financial events unfold on our television schemes.

“Whatever our anxieties about our party, it is to focus on the needs of our country. It is time to stop looking inwards and to look outwards at the needs, the interests and the problems of the British people.”

Mr Miliband said Mr Brown was the “right leader” to deal with the turbulence in the economy. “In these tough times, I’ll tell you the qualities you need. You need resolve, you need toughness and you need a deep sense of fairness and Gordon Brown has all those qualities."

In his welcoming speech Sir Richard Leese, Labour leader of Manchester City Council, also said Mrs Brown had to be allowed to give his “undivided attention” to the economic turbulence facing Britain. The party could only win the next election if it had “discipline and unity”.

“What the people of Britain expect - and they will not forgive us - if we spend our time in unseemly squabbling when there is a more important job to do.

Also today 20 Labour MPs sent a letter to all their parliamentary colleagues urging them to “stand up and be counted” by joining the loyalist campaign launched by former Deputy Prime Minister John Prescott to secure a fourth term in power.

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