The Crown Prosecution Service yesterday announced that it would mount a "comprehensive" review of phone-hacking material held by the Metropolitan police in a dramatic volte-face prompted by recent revelations in the courts.

The CPS review will also examine other evidence that has emerged since the trial of the News of the World's former royal editor Clive Goodman and private investigator Glenn Mulcaire, including revelations published by the Guardian which suggest that phone hacking was rife at the paper.

It is thought that the CPS may be preparing to adopt a wider interpretation of the laws that make hacking into phone messages an offence. That would make it easier to bring new prosecutions and secure convictions.

Previously the CPS has applied a very narrow definition, using that to explain its reluctance to pursue other cases, despite holding evidence that could prove that senior journalists at the NoW authorised the hacking of phones belonging to scores of public figures.

The CPS had been of the view that an offence of phone hacking would require it to be proved that someone had hacked a phone and listened to a message before the owner of the phone had a chance to hear it. Now the CPS believes an offence may have been committed if a phone was hacked and a message listened to by a journalist or private investigator at any time, even if the owner had already heard it.

The change increases the chances of a fresh police inquiry, with past and present employees being investigated, though some informed sources believe that the chances of enough evidence being found to bring a charge still remains low.

Keir Starmer, the director of public prosecutions, summoned John Yates, acting deputy commissioner of the Met, to a meeting yesterday where the move was agreed.

The DPP's move increases the pressure on Andy Coulson, David Cameron's director of communications, who resigned as NoW editor in January 2007 after Goodman was jailed for illegally intercepting voicemail messages. Because Goodman and Mulcaire pleaded guilty, the level of evidence a jury would need to convict was not fully tested.

Coulson has always maintained he knew nothing about Goodman's actions and executives at News International, part of Rupert Murdoch's media empire, have said he was a "rogue reporter" acting alone.

Last night, News International was scrambling to obtain further details from the CPS about the nature and scope of its inquiry. An insider pointed out that it was carrying out "an assessment rather than an investigation". A spokesman for NI said: "The News of the World will continue to co-operate with any request from the police or the Crown Prosection Service."

The CPS said last year that the case had been closed following a month-long review of evidence held by Scotland Yard. It said yesterday the new review had been prompted by "developments in the civil courts", where several victims of phone hacking are pursuing legal action against News Group, the News of the World's parent company, for breach of privacy.

They include the actor Sienna Miller, football agent Sky Andrew and Nicola Phillips, a celebrity publicist who used to work for Max Clifford.

Those cases, which are currently going through the courts, are shedding more light on the affair and cast doubt over the paper's version of events. Miller's lawyers have obtained Mulcaire's notes, which were seized by the Met in a raid on his home in 2006 and led to his successful prosecution. They show that Mulcaire wrote "Ian" in the margins of transcripts he made of voicemail messages he retrieved from Miller's phone and those of her associates. Her lawyer's contend that "Ian" is a reference to Ian Edmondson, the News of the World's assistant editor (news).

It emerged last week that Edmondson had been suspended before Christmas after his name emerged in the court documents. He is now the subject of an internal investigation. Senior CPS lawyers were unaware of the material relating to Edmondson before it was revealed by the Guardian. One senior legal source said the material could amount to circumstantial evidence that he knew what was going on at the paper. While not enough on its own to prosecute, it might be enough for the CPS to advise Scotland Yard to reopen its investigation and hunt for executives at the NoW who knew about hacking.

News International has fought hard to prevent further details relating to the phone-hacking scandal from becoming public by reaching out-of-court settlements with other litigants. It paid £1m to Clifford last year.

The Guardian revealed in July 2009 that it had also paid a total of £1m to Gordon Taylor, the chief executive of the PFA, and two other people.

Mark Lewis, the lawyer who acted for Taylor and is representing Phillips, said: "The police have consistently said they would investigate any new evidence that become available. But this is not about new evidence – it has always been about looking at the old evidence properly."