British lawmakers launched a furious, multipronged barrage of questions Wednesday at Bob Diamond, who resigned as the head of Barclays a day earlier, but Diamond steadfastly defended himself and the bank.

Diamond refused to be drawn into whether he would give up millions of dollars' worth of bonuses, and he insisted the scandal that forced him to quit was due to a small number of "reprehensible" traders at Barclays.

The banker said he became "physically ill" when he found out about the scandal -- something he said he learned only last month.

"The behavior was wrong. It's been eradicated. It's been dealt with," he insisted.

Diamond stepped down Tuesday as chief executive of Barclays amid the scandal that also claimed two other executives at the bank this week.

He insisted Wednesday at a parliamentary hearing that history would judge the bank as "an incredible institution."

But lawmaker Andrea Leadsom, herself a former Barclays banker, accused Diamond of living in a parallel universe, saying the culture of Barclays was the problem, not the solution.

And Teresa Pearce, another member of the Treasury Select Committee, attacked his line of defense.

"You just keep saying, 'I didn't know, I didn't know,' " about wrongdoing at his bank, she said.

She pressed him on an infamous comment he made to lawmakers last year to the effect that it was time for bankers to stop apologizing for their actions.

"It did not come across in a way that was positive or the way I meant it," Diamond said after quibbling with her about when he made the remark.

He also brushed aside angry questions from lawmaker John Mann about whether he would give up bonuses or donate them to charity, saying decisions had not yet been made.

British and American regulators fined Barclays more than $450 million last week for rate-fixing during the height of the global financial crisis.

The scandal centers on the rates at which banks lend each other money. The rate is hammered out based on input from big banks in London each morning and is known as the London interbank offered rate, or Libor.

It affects how much interest ordinary people pay on everything from credit card debt to home mortgages and student loans.

The fine came after Barclays admitted some of its trading desks purposely underreported its interest rates.

Former investment banker Ralph Silva said the scandal has caused such fury because of its impact on the public.

"If they're manipulating Libor, what they're basically doing is taking money out of the public's pocket," he said.

Diamond said Wednesday he was "sorry, I'm disappointed and I'm angry" about the rate-fixing. "This was wrong and I'm not happy about it, but we put all the resources we could to make sure it was dealt with. ... This doesn't represent the Barclays that I know and I love."

He blamed the wrongdoing on 14 traders out of "a couple thousand."