Scotland Yard is to consider fresh claims that a top Tory aide was involved in a phone hacking scandal, following criticism from a West Midlands MP.
Tom Watson (Lab West Bromwich East) is leading calls for an inquiry into Conservative spin doctor Andy Coulson.
Mr Coulson, a former editor of the News of the World, has denied he knew journalists at the newspaper were hacking the mobile phones of celebrities and politicians.
But Mr Watson and other Labour MPs claim the Metropolitan Police have failed to investigate the affair properly.
And he succeeded in forcing Theresa May, the Home Secretary, to answer questions about the affair in the House of Commons.
Mr Watson told her: “The integrity of our democracy is under scrutiny around the world. The Home Secretary must not join the conspiracy to make it a laughing stock.”
Mr Coulson resigned from the paper in 2007 after the former royal editor, Clive Goodman, and a private investigator used by the paper were jailed for plotting to intercept voicemail messages left for royal aides.
A court was told the pair hacked into the voicemails of famous people, and used the information they obtained to write newspaper stories.
Mr Coulson has always said he knew nothing about it, and went on to become Director of Communications for the Conservative Party. He is now a government special adviser, working in Downing Street.
Police said they could re-open inquiries after former News of the World journalist Sean Hoare claimed Mr Coulson knew of eavesdropping tactics used at the newspaper during his time in charge.
Mr Watson has written to Sir Paul Stephenson, Commissioner of the Metropolitan Police, as well as Nick Clegg, the Deputy Prime Minister, demanding they look into the claims.
Metropolitan Police Assistant Commissioner John Yates said: “It is new and we will consider it and be consulting with the Crown Prosecution Service before we do.”
The affair has the potential to cause significant embarrassment for David Cameron, as suggestions that Mr Coulson has done anything wrong call into question the Prime Minister’s judgement in appointing him to a senior government position.
A spokesman for Mr Coulson said: “Andy Coulson has today told the Metropolitan Police that he is happy to voluntarily meet with them following allegations made by Sean Hoare.”