Rupert Murdoch: facing growing unrest among News International journalistsCredit: Lewis Whyld/PA
The News Corporation chairman and chief executive landed in the UK last night on a private jet at Luton airport and will head to the newspaper group's Wapping headquarters in London later.
His visit to the UK comes after 10 current and former Sun journalists and executives were arrested and bailed in a Metropolitan police investigation into alleged payments to police and other public officials.
Murdoch is expected to reiterate his pledge to keep publishing the Sun, which has been the subject of sale or closure rumours since last weekend's arrests.
There is said to be growing unrest at News International about the way News Corp's management and standards committee (MSC) has been working with police.
The National Union of Journalists has described the work as heavy-handed and has voiced concern that journalists' sources are being compromised. The MSC says it is carefully redacting documents.
Sun associate editor Trevor Kavanagh said earlier this week: "There is unease about the way some of the best journalists in Fleet Street have ended up being arrested on evidence which the MSC has handed to the police."
Society of Editors director Bob Satchwell said journalists he had spoken to were concerned because "they don't know precisely where this police inquiry is going".
He told BBC Radio 4's Today programme: "You're getting to a stage where there is a chilling effect on journalism.
"The problem is that ever since this story started going we've had a lot of conjecture, a lot of allegations and precious little solid evidence.
"What we've got to avoid is journalism itself being damaged."