London, England (CNN) -- London's Metropolitan Police said it might reopen an investigation into the alleged hacking of phones of top British politicians and celebrities by a tabloid newspaper, even as it defended its original probe.
A News of the World journalist and a private investigator were sentenced to prison in 2007 for hacking into voice mails of members of the royal family's staff. The private investigator also admitted hacking into model Elle MacPherson's messages, among others.
But the New York Times alleged in a detailed investigative piece that -- far from royal reporter Clive Goodman and private investigator Glenn Mulcaire being lone culprits -- phone hacking was common practice at the newspaper.
The allegation could have a direct effect on the British government because the editor of the paper at the time was Andy Coulson, who is now British Prime Minister David Cameron's top communications aide.
Coulson resigned from the News of the World when his reporter was imprisoned, but has always insisted he did not know about the practice.
Cameron's office Saturday reiterated Coulson's insistence that he didn't know about the illegal phone hacking at his paper.
"Andy Coulson, Downing Street Head of Communications, has repeatedly denied any knowledge of phone hacking," the prime minister's office said in a statement.
The New York Times article last week prompted a furious response from a number of public figures, including former deputy prime minister John Prescott, who demanded that the police tell him if his phone had been hacked.
"The newspaper produced no new evidence for us to consider reopening the case," Assistant Commission John Yates of the Metropolitan Police said late Sunday. "We have always said that this position could change if new evidence was produced."
Yates then went on to say the New York Times did, in fact, include information they were not previously aware of -- on-the-record statements from former News of the World journalist Sean Hoare.
Hoare told the Times that Coulson, then his boss at the tabloid, "actively encouraged me" to hack into the voice mails of public figures to get stories for the News of the World.
The prime minister's office said Coulson has offered to meet with Metropolitan Police "if the need arises, and would welcome the opportunity to give his view on Mr. Hoare's claims."
Coulson's allies have cast doubt on Hoare's credibility since the Times article came out September 1, pointing out that Hoare was fired from the paper over allegations of drug and alcohol abuse.
The New York Times also alleges that the police did not pursue their investigation into the News of the World as aggressively as they could have, both because of a "symbiotic" relationship between the police and the paper and because they were busy with other investigations.
Assistant Commissioner Yates did not respond to those allegations in his statement late Sunday.
The News of the World Saturday rejected "absolutely any suggestion there was a widespread culture of wrongdoing" at the paper.
A British parliamentary committee twice investigated the tabloid. Witnesses associated with the paper insisted there was no evidence that phone hacking extended beyond the two who were found guilty of it.