Gordon Brown’s closest ally told Labour critics yesterday to stop their “indulgent nonsense” and ignore the “disappointeds” who talked the language of defeat.

In an outspoken interview with The Times, Ed Balls said that Labour must not fall for false prophets, and gave warning that Labour would be “intolerant” of anyone who put personal interests and disappointments before the party’s and the country’s.

There would always be people who “have a gripe, a score to settle and disappointments from the past – it was ever thus”, said Mr Balls, the Schools Secretary.

Labour was trying to win back power in local elections in places such as Merseyside, Birmingham and Leeds. “The efforts of local councillors and shadow leaders should not be undermined by this kind of indulgent nonsense. Rather than cause difficulties for the party, Labour will feel that these people should get out on the campaign trail and start fighting the Conservatives and the Liberal Democrats.” Of his leader, Mr Balls said: “Anybody who has the strength and conviction to take the tough decisions he did on public spending in his first two years, resist pressure to go into the euro and deal with fears of recession in 1998 and 2001 shows that he knows how to handle difficult times.

“When times are tough is when experience counts. When times are tough is when unity of the party is at a premium. When times are tough, having ideas and policies for the future really matters.”

The comments were particularly aimed at the Labour figures who, Mr Balls believes, have privately briefed against Mr Brown, even suggesting that he might go and that Charles Clarke may run as a stalking horse. He denounced the “silly gossip” that Labour figures have fed to newspapers during the Easter recess.

Mr Balls also defended himself at a time when he has become embroiled in controversy over naming and shaming schools that are said to have broken the new admissions code. Mr Balls has been accused of conducting a witch-hunt against faith schools, of a “near-criminal” attack on high-performing schools, and of positioning himself for a future leadership challenge.

He strongly denied the charges laid against him, and mounted a vigorous defence of the Prime Minister who, he said, had gone through tough times before.

Asked whether he now regretted that Mr Brown had not gone for an early election, Mr Balls said that he saw no point in looking backwards or regretting decisions like that: “What we have to do is fight a good election campaign and work across Government to show we are focused on delivering our mission of change.”

He brushed aside suggestions that the malcontents were taking revenge on Mr Brown for his own allies causing trouble for Tony Blair. Instead Mr Balls emphasised the ideological unity of his party. He said that governments under midterm pressure go on to lose elections because they have mismanaged the economy, are ideologically divided and lose touch with the concerns of voters. Mr Balls said although he was not complacent, the Government should not fail on any of those counts. The doom merchants “need a reality check”.

Mr Balls laughed off suggestions that he was a “class warrior”. He said he had spent ten years at the Treasury, where he was part of the drive to open up the markets and promote enterprise and entrepreneurship. He was City Minister, where he travelled the world promoting London’s role as a dynamic enterprising centre. “I do not think anybody who met me in New York or Frankfurt or Tokyo would have thought that this was a class warrior they were meeting.”

He also compared the Big Bang reforms in the City in the 1980s to what he was trying to achieve in education, including the controversial changes to the admissions code. The City was great as a financial centre because in the 1980s it accepted that if it was to become world-class, restrictive practices had to be removed and the system had to be opened up to talent, entrepreneurship and new opportunities, Mr Balls said. There was a parallel in education.

“I will refute any charge that I am for anything other than excellence. I and every parent want their children to go to an excellent school and have the best chances. But there is a choice as a society. Are we simply about preserving excellence for those who have it or are we determined to make sure that excellence and opportunity is open to all?

“What we are doing in having education to 18, curriculum reform, the admissions code, is putting in place big reforms to open up opportunity for all. The City of London would never have flourished in the 1990s unless we had had the reforms of the 1980s. I do not think as an economy and education system we will be excellent unless we use the talents of everyone. The dividing line between the parties is the difference between preserving excellence for some or opening up excellence for all. I am determined to fight the battle for excellence for all.”

Mr Balls said that he did not regret the way he handled the school admissions review, which suggested that one in six state schools might be breaching the new admissions code, with some asking parents for “voluntary contributions” worth hundreds of pounds on their application forms. The majority of offenders were said to be faith schools.

Ministers had thought very hard about how the review should be handled in February and March and he had not asked for the work to be done with the intention of publishing it. But when the information came it showed they were not making the kind of progress they would have liked on the code in the last year, he said. It was serious information about what was happening for parents.

“The judgment we took after legal advice from a QC was that to sit on this information would have been totally irresponsible. We judged we could not make it public until we had verified it. But to have gone through the verification process without having made public what we were going to do would have been wrong. We took a QC’s advice on what our legal obligations were. We looked very carefully at this because we were worried about what we had found.

“We did not want to disrupt the admissions process but we wanted to know what the position was. We judged it was right to let the admissions process proceed and make the information public for parents. It would be wrong to conceal it and we wanted to make sure the coming admissions process was better.

“Of course it has been misrepresented politically by some. I had detailed discussions for months on this with all of the faith leaders and local government and teachers. What we have done is ensured there had been much great focus now on getting the admissions arrangements right.

Local authorities and diocesan officials are now very well aware of their responsibilities.

“People will look back and say we have made a decisive step towards fair admissions. We decided the responsible thing was to act. We had clear evidence that for many thousands of parents the arrangements had not been as fair as the code required.”

Frank Field, the Labour MP, had called his moves “near-criminal” and others suggested that Mr Balls was positioning himself for a leadership battle. The latter charge was “absurd”, he said. “I have a responsibility to parents and children. My responsibility is to ensure the admissions code is implemented and that admissions are fair and according to the law. The question I asked myself was whether I had done enough to fulfil my responsibilities to parents and whether the law had been followed.

“I fully respect the views of everyone, including those who disagree with me. If Frank looks at what we are doing and talks to diocesan leaders, he will see it is the right thing by faith schools.”

Mr Balls said he was not denying that for some schools it was stressful and uncomfortable and in many cases they would feel that they should have had more advice from the local authorities on what the code required.

It would have been wrong to suppress that information, he said. If a parent had found out afterwards that the Secretary of State had known the information but not made it public he would not have felt the minister was on his side.

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