George Osborne has refused to apologise for attempting to introduce "upsetting" cuts to disability benefits before doing a U-turn on the plans.
The Chancellor insisted he had listened to and learned from concerns about the cuts to the personal independence payment (PIP) and dropped the proposal.
But he did not accept former shadow chancellor Chris Leslie's invitation to say sorry for the mistake which left a £4.4 billion hole in the Budget.
Mr Osborne was taking the unusual step of opening the final day of debate on the Budget to respond to widespread concerns following Iain Duncan Smith's explosive resignation from the Cabinet.
It is believed to be the first time a chancellor has done so for two decades, when Ken Clarke occupied 11 Downing Street.
He was asked by Mr Leslie in the Commons: "It's less than a week since you stood up in that Budget and made that decision affecting disability independence payments, something that upset many hundreds of thousands of people across this country.
"You have made a welcome U-turn, but shouldn't you now acknowledge that was a mistake that you should say sorry for?"
Mr Osborne replied: "I'm going to come on and speak about the disability benefits and the way forward.
"But I have made it clear that where we've made a mistake, where we've got things wrong, we listen and we learn.
"That's precisely what we've done."