Pensioners are already paying back benefits they do not need, Iain Duncan Smith claimed today.

The Work and Pensions Secretary defended his remarks over the weekend when he said he would ''encourage'' people to forego perks such as free TV licences and winter fuel payments.

Coalition ministers yesterday traded blows over the comments but today Mr Duncan Smith described himself as ''relaxed''.

He told Radio 4's Today programme: ''It was in answer to a question which was 'what if they don't need it or don't want it?'

''My answer is if they don't want it or don't need it there has always been on the website a helpline.

''If they want to go and ring that and make arrangements to pay back we have already been taking money from people who want to do that anyway.

''We did that on the basis of people who asked us to do that.''

Yesterday Deputy Prime Minister Nick Clegg responded by attacking the Tories for blocking means-testing of the benefits.

And Mr Duncan Smith's Conservative Cabinet colleague Ken Clarke said he did not believe it was even possible to return money to the Government.

But the Work and Pensions Secretary said that his comments had been ''twisted''.

''I think that it's right for them to keep whatever they want to keep, it's up to them, I am absolutely proud of what we have done,'' Mr Duncan Smith said.

''Honestly, you shouldn't try and twist what I'm saying. I said categorically I neither want them to give it back or keep it. If they are eligible for it it's wholly their money to take as they wish.

''It's right to give them this money, pensioners are vulnerable and they need to know they have a security of payment over a long period of time.''

Asked if David Cameron supported Mr Duncan Smith's call for wealthy pensioners to hand back the payments, the Prime Minister's spokesman said there was a Government commitment to protect the universal benefits.

He said: ''The Prime Minister's view on this is very simple. He made a promise, he made a commitment that we we would retain these benefits and that they would stay in place.

''That is in the coalition agreement. There are absolutely no plans to change that, that's very much his view on the matter.''