Labour leader Ed Miliband has accused David Cameron of "bringing a criminal into the heart of Downing Street" after Andy Coulson was found guilty of phone hacking.
Mr Miliband said the Prime Minister owed the public an explanation for what he described as a "serious error of judgment."
He said: "I think David Cameron has very, very serious questions to answer because we now know that he brought a criminal into the heart of Downing Street.
"And David Cameron was warned about Andy Coulson, the evidence mounted up against Andy Coulson, David Cameron must have had his suspicions about Andy Coulson, and yet he refused to act.
"I believe this isn't just a serious error of judgment. This taints David Cameron's Government because we now know that he put his relationship with Rupert Murdoch ahead of doing the right thing when it came to Andy Coulson."