The Andy Coulson phone hacking scandal shows no signs of dying down as Gordon Brown revealed that he thought his phone was being hacked during his time as Chancellor.

As prime minister, Brown wrote to Scotland Yard telling them that he suspected his phone had been hacked. However his letter got no response.

Gordon Brown is the most senior figure involved in the scandal as pressure is now mounting for Scotland Yard to re-open the investigation.

PM David Cameron’s top spin doctor, Andy Coulson, was forced to resign from his Downing Street job on Friday amid allegations about phone hacking while he was editor of News of the World.

In 2007, Coulson quit as editor of News of the World after the paper’s royal reporter admitted hacking royal phones.

Coulson has consistently denied having any knowledge of phone hacking, blaming a “rogue” News of the World reporter. However these claims have been increasingly ridiculed and he quit No 10 on Friday, admitting he could not do his  job properly.

The list of those claiming that their phones were hacked by News of The World journalists continues to grow. Politicians, including Peter Mandelson and John Prescott, and celebrities including actress Sienna Miller, are taking civil court action over allegations their phone messages were hacked.

Gordon Brown’s allegations will bring the matter even more into the spotlight.

Brown apparently wrote to Scotland Yard last year asking whether his phone number had been among the records of those targeted by tabloid newspaper stings. His letter went unanswered.

The police’ handling of the affair is being questioned.

Tony Blair’s former Downing Street spin doctor Alastair Campbell said: “When you compare and contrast the way the police pursued Tony Blair on the so-called cash-for-honours nonsense and the lacklustre way in which they handled this, there is a very big difference.

“There must be reasons behind that which will, I think, become part of an unfolding scandal.”

Ministers are being urged to order an independent inquiry into the actions of the Metropolitan Police.