* UK prosecutors to give update on hacking inquiry charges
* Murdoch confidante and ex-Cameron media chief await announcement
* Allegations of corrupt payments at two more UK newspapers
By Michael Holden
LONDON, July 23 (Reuters) - Rupert Murdoch's former British newspaper boss and Prime Minister David Cameron's ex-media chief could find out on Tuesday whether they will be prosecuted in a phone-hacking inquiry that has shaken the British establishment.
Rebekah Brooks, who ran Murdoch's UK papers and was courted by successive British leaders, is the most high profile figure to be arrested during an investigation into allegations newspapers listened to the private messages of royals, celebrities and even a teenage murder victim.
The scandal has rocked Murdoch's News Corp, put the notoriously aggressive press under the spotlight and embarrassed senior politicians, including Cameron, over their often cosy ties with the Australian-born businessman.
Cameron's former communications chief Andy Coulson, who also edited Murdoch's now defunct News of the World, is among about a dozen of the paper's former staff awaiting an update on their cases from prosecutors at 1000 GMT on Tuesday.
Britain's Crown Prosecution Service will give details of any criminal charges in the hacking inquiry, although a final decision on every case may not be announced.
Brooks has already been charged with conspiracy to pervert the course of justice, accused of hindering the police investigation into phone hacking and corruption by staff at his British tabloids.
The detective leading the hacking inquiry said earlier a parallel investigation into corrupt payments by journalists would be extended beyond Murdoch's British newspaper business to other publishers.
Since January last year, police have been working with Murdoch's News International, part of News Corp, to uncover wrongdoing among its staff over allegations journalists illegally accessed mobile phone voicemail messages.
That inquiry has since been expanded to look at corrupt payments to public officials and allegations of computer hacking.
News International has been particularly hit by the repercussions. Murdoch abandoned a bid to acquire the whole of the lucrative pay-TV group BSkyB, which would have been the biggest deal in News Corp's history. He also closed down the 168-year-old News of the World Sunday tabloid.
On Saturday, News Corp announced Murdoch was stepping down from a string of boards overseeing his British papers, reigniting speculation they might be sold.
"We believe his resignation is linked to the planned spin-off of the company's newspaper and other publishing businesses," ratings agency S&P said on Monday, adding the move had had no impact on its rating of the company.
Now rival tabloids could face the same scrutiny over payments. Deputy Assistant Commissioner Sue Akers said the focus of her investigation was being extended to examine allegations against reporters at Trinity Mirror which publishes the Daily and Sunday Mirror, and Express Newspapers, which publishes the Daily and Sunday Star titles.
"Our ongoing investigation has recently revealed that in some cases where we've identified a public official who's received payments from News International, we've also established they have received payments from other newspapers," she told a public inquiry ordered by Cameron into media ethics.
Akers said their probe had discovered that a prison officer at a high security jail had been paid 35,000 pounds ($54,300) by News International, Trinity Mirror and Express Newspapers between April 2010 and June 2011.
Stories relating to the payments had been identified in the Mirror and Star papers, the inquiry heard, while another prison officer had received 14,000 pounds from Trinity Mirror.
"The majority of these stories reveal very limited material of genuine public interest," Akers said.
About 160 officers are examining reports that journalists at the News of the World routinely hacked into the phones of hundreds of celebrities, politicians and victims of crime to generate front-page stories.
Akers said they had notified 2,615 people who might have had their phone hacked, of which 702 were likely to have been victims.
The three investigations have led to more than 60 arrests including dozens of current and former journalists, some of whom held senior positions at News International titles.