A few weeks ago Hilary Benn’s father told him that he had something that might help him in the coming Labour deputy leadership contest.

“I think you might need these, H,” Tony Benn said. “H” is what he calls him. He gave him several plastic “Benn for Deputy” badges, which Benn Sr had used in the 1981 deputy leadership fight.

Twenty-five years later, Hilary Benn is one of the favourites to take the post that his father failed to win by less than 1 per cent in the contest in which he was beaten by Denis Healey.

Tony Benn was then running on the kind of platform — nationalisation of the commanding heights of the eco- nomy, withdrawal from the European Union and unilateralism — that would make new Labour, to which Hilary is a fully signed-up member, shudder.

His son backed him then, but was it out of family loyalty or because he thought his father was in the right place politically? “Absolutely for both reasons,” he told The Times.

But would it have been a good thing for the Labour Party if his father had won? That appears to be a different matter. “I am not going to go back over history,” Mr Benn said. “You have to deal with things as they are at the time.”

He recalls events that show why he and Labour have changed. He remembers when standing in Ealing in 1983, a time when Labour was committed to taking over private employment agencies, that a woman stood up at a meeting and explained how she had worked hard to set up her agency and was providing work for many people, and had asked why he wanted to take away her livelihood.

“I remember thinking at the time, ‘No wonder she is not going to vote for us because she thinks Labour is not in the business of supporting people like her.’ That is an example of the process we had to go through.”

Today there is no more loyal member of the Cabinet. In the course of the interview Mr Benn heaped praise on Mr Blair, Gordon Brown, whom he wants to be leader, and John Prescott, whom he wants to succeed as deputy leader, although he makes plain that he is not running to be deputy prime minister.

What would he bring to the job of deputy leader? “I think we need as deputy leader someone who can give leadership and offer advice, someone who will ensure that the voice of the party and the unions get heard in the upper reaches of government. We need someone who is good at listening and good at working with others.

“It has to be someone who can show the party’s passion for social justice both at home and abroad. There are big challenges ahead in terms of globalisation, climate change and insecurity; and people are looking for political leadership which shows that it can handle the process of change. That is what the Labour leadership must be offering to people.”

Would Mr Benn be strong enough to tell a leader such as Mr Brown what he did not want to hear? “I think implicitly that is part of the role. The deputy has to provide good advice and to ensure that other people’s views are heard.”

Mr Benn did not offer an opinion on whether Mr Brown should be given a clear run. “That is in the hands of the party, but I am clear in my own mind that Gordon should be, and will be, the next leader and Prime Minister.”

Mr Brown, he said, is a towering figure who thinks very deeply about politics and knows how to use the opportunity that political power brings with it. “He gives vivid expression to the passion for social justice that is our defining characteristic.”

Is Mr Benn a moderniser? “I am very averse to labels. If I think something is the right thing to do then I will do it and I will make the case for it.” He may be helped by most of his government career having been at International Development, an area that tugs at his party’s heartstrings, although he emphasised that he has to argue his case for funding just like the rest of the Cabinet and had a year in the challenging job of Minister for Prisons and Probation.

He believes that the party will show unity in the coming months in the face of a stronger Tory threat. “The Tories are the most successful political party in British history and we underestimate them at our peril. But at the moment we know almost nothing about what David Cameron’s programme would be. The last two Labour governments ran into trouble with the economy.

“The achievement of the past ten years has been the success of the economy and I think a lot of voters will ask themselves when they vote next time whether they want to put that at risk.”

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