LONDON - British Prime Minister David Cameron, defending his integrity in an emergency debate in parliament on Wednesday, said he regretted the uproar caused by his hiring of a former newspaper editor at the heart of a phone-hacking scandal.

Under pressure from opponents to apologize, he said Andy Coulson, his former spokesman who once edited Rupert Murdoch's News of the World, had denied knowing of phone-hacking by the paper. But should Coulson turn out to have lied, the prime minister said he would then offer an apology.

Beleaguered but not seen under serious threat of being dumped by his party after less than 15 months in office, Cameron defended his actions and those of his staff in dealings with the police and Murdoch's News Corp media empire.

But the 44-year-old Conservative premier said after his toughest two weeks in power: "You don't make decisions in hindsight; you make them in the present. You live and you learn - and believe you me, I have learned."

Cameron, who cut short a tour of Africa as parliament delayed its summer recess to quiz him, said in his opening statement: "I have an old-fashioned view about innocent until proven guilty. But if it turns out I have been lied to, that would be a moment for a profound apology. And, in that event, I can tell you I will not fall short."

Murdoch sent a message to his staff that his company was taking steps to ensure that "serious problems never happen again".

"Those who have betrayed our trust must be held accountable under the law," he added in an e-mail sent late on Tuesday.

Analysts said Murdoch's televised apology had put the spotlight on how Cameron emerges from scrutiny in the emergency parliamentary debate over the scandal, which has included allegations of hacking into a murdered schoolgirl's voicemail and the phones of British troops killed in combat.

A new opinion poll by Reuters/Ipsos MORI showed Britons' satisfaction with Cameron had fallen to its lowest level since he entered office in May last year. Only 38 percent were happy with the way he was doing his job. Another cross-party parliamentary committee published a report criticizing both News International and the police over the phone-hacking investigation.

Reuters