Current and former editors of Rupert Murdoch's The Sun say it can be a "powerful force for good" British Prime Minister David Cameron on Tuesday said he would appear before the country's phone-hacking inquiry if asked, following reports that he will be summoned to explain his links to Rupert Murdoch.
Cameron himself ordered the Leveson inquiry amid a spiralling scandal over the illegal hacking of mobile phone voicemails by the News of the World, Murdoch's British Sunday tabloid, which was shut down in July.
Responding to a report in Tuesday's Times newspaper, which claimed he was "99.9 percent certain" to be summoned, Cameron's Downing Street office said "of course he would attend", but no request had been received yet.
Lord Leveson is also expected to invite Cameron's predecessor, Gordon Brown, and current Labour Party leader Ed Miliband, the Times reported.
"I can't see how you can look at the relationship between the press and politicians without talking to top politicians, including the prime minister, the previous prime minister and the leader of the opposition," a source close to the inquiry told the paper.
The prime minister is likely to be quizzed over his 26 meetings with Murdoch executives and about his hiring of ex-News of the World editor Andy Coulson, who resigned from the paper in 2007 over the scandal.
The Daily Telegraph's Tony Gallagher, Lionel Barber of the Financial Times and the Independent's Chris Blackhurst are all due before the inquiry later Tuesday to answer questions concerning ethics, fact-checking and complaints.
Current and former editors of Murdoch's tabloid The Sun defended the newspaper at the inquiry on Monday, saying it could be a "powerful force for good".
Staff at Britain's best-selling newspaper told the inquiry in London that they had seen no evidence that the The Sun was guilty of the hacking that led to the closure of its weekly sister paper the News of the World.
Kelvin MacKenzie -- who as Sun editor from 1981 to 1994 presided over colourful headlines such as "Gotcha", about the sinking of the Argentine warship General Belgrano during the Falklands War -- said the paper had since become more cautious.
"Towards the end of my time as editor I was less bullish than I was, perhaps, during the '80s," MacKenzie said.
"The editors (now) are more cautious and were probably right to be cautious."
He admitted some previous mistakes. In 1992, he had told then-prime minister John Major he was going to "throw a bucket full of shit" over him in the following day's paper after Britain left the European Exchange Rate Mechanism.
 And MacKenzie said Murdoch was furious when The Sun had to pay £1 million in the late 1980s in libel damages to singer Elton John, saying that he had received 40 minutes of "non-stop abuse" by telephone from the Australian-born tycoon.
Dominic Mohan, who has edited The Sun since 2009, said the paper could be a "powerful force for good" through its campaigns, support for charities and efforts to explain complex concepts in clear language.
The former showbiz reporter brushed off a comment he made in 2002 about phone-hacking at a rival tabloid, the Daily Mirror.
He said it was a "cheap shot" and a "joke" at the expense of then editor Piers Morgan, who now fronts a talk show on US-based news network CNN and denied phone-hacking when he appeared at the inquiry last month.
The paper's current royal editor Duncan Larcombe meanwhile told the inquiry, led by senior judge Brian Leveson, that he contacted Buckingham Palace before running any exclusive story on the royal family.
The scandal has also threatened to engulf the The Sun, which has itself faced legal action for alleged phone hacking. It denies the allegations.
A string of people has been arrested over the phone-hacking scandal, including former Sun editor and News International boss Rebekah Brooks, and Coulson, who went on to become Cameron's spokesman.
Brooks' former personal assistant was reportedly arrested last week on suspicion of deleting emails belonging to News International, the British newspaper arm of Murdoch's empire.