Alistair Darling has told the Politics Show that nuclear power will be part of Britain's energy supply, ahead of the government unveiling its plans for the future of the UK's energy next week.
The Trade and Industry Secretary, Alistair Darling, told Jon Sopel:
"I advocate the case for reducing our demand for energy, for having more wind farm capacity, more renewables and I'm going to be announcing changes that I think will encourage even more renewable electricity but I also think there ought to be a mix."
When pressed on what proportion of the UK's energy supply nuclear should comprise, he said it would be up to the private sector to determine.
"The reason I'm not saying that there ought to be such and such a percentage of that mix is because at the end of the day that has to be up to the power companies.
"But the question actually this week is do you say no to nuclear under any circumstances and I don't think that's a sensible policy."
He added: "I don't have a firm number in my mind as to the actual proportion or the number of power stations.
What I do know is that you do need a mix and of course there's another reason too.
The trouble with renewables is they're very good in providing you with low carbon electricity generation, but of course on very hot days or very cold days, if the wind doesn't blow, then you would have a big problem, and that's where nuclear has provided a base load of electricity for many years now."
Talking about Gordon Brown's character, Mr Darling defended his friend on charges of being grumpy:
"Gordon, who I have known for a long, long time, you know, is a smiley person, as well as sometimes as the austere Chancellor, giving a different image.
"As I said, he is a thoroughly decent man. He's got a very clear sense of what's right, what's wrong.
"He's got a very clear sense of fairness right from, you know the time he was growing up, he's always been very clear that it was the job of government to encourage people to do the best they can for themselves and their families, to get on.
"And you know, I've known Gordon, for many, many years. He is really good company, he's good fun to be with.
"You know, I think sometimes when you're Chancellor, you do have to be grumpy and he was a very good Chancellor.
"Well to be the Chancellor you have to be grumpy from time to time, er but you know, I think you also you know, have to smile, have a smile on your face.
"I think you know sometimes people get a little bit obsessed about these things about politicians, do we smile too much, are we you know, grumpy, do we look boring, you know?"
"I think you know most people have got more sense than that."
The Politics Show Sunday 20 May 2007 at 12:00 BST on BBC One.
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