Prime Minister David Cameron has said that "with 20/20 hindsight" he would not have hired Andy Coulson as his chief media adviser.
Speaking in an extraordinary session of parliament on Wednesday, Cameron said he would give a "profound apology" if Coulson, a former News of the World editor who has been arrested and bailed in connection with phone hacking, was proven guilty.
"I regret and I am extremely sorry for the furore it has caused.
"With 20/20 hindsight and all that has followed I wouldn't have offered him the job and I expect that he wouldn't have taken it.
"But you don't make decisions in hindsight, you make them in the present. You live and you learn and believe you me I have learnt," he said.
Cameron began the session with a statement over the row, addressing parliament about the "torrent" of allegations surrounding the media, police and politicians over the phone hacking scandal.
He outlined the details of the judge-led inquiry into the scandal and listed the panel members who will sit in on the investigation, which will examine police corruption and regulation of the press.
They will be: Director of Liberty Shami Chakrabarti, Former CC West Midlands Sir Paul Scott Lee, Former DIrector of Ofcom Lord David Curry, former political editor of Channel 4 News Elana Goodman, former political editor of the Daily Telegraph George Jones and former chairman of the Financial Times Sir David Bell.
Cameron facing tough questions over allegations that a former News of The World executive arrested in connection with phone hacking advised Coulson before he was elected.
In his address the prime minister said the Conservative party had never employed Neil Wallis, who also worked as a PR consultant to the Metropolitan police, or his company.
But he said Wallis may have provided Coulson with "some voluntary advice" before the election. "I did not know anything about this until Sunday night" he said.
He also defended Ed Llewellyn, his chief of staff, who was accused of blocking the Metropolitan police from informing Cameron about the scandal last year.
More to follow.