Damian McBride, Gordon Brown's former spin doctor, has claimed that he was offered "double" the money by an unnamed publisher to delay his book until the 2015 election in order "to do maximum damage to the Labour party".

McBride was paid about £130,000 by the Daily Mail to serialise his memoirs published on the eve of the Labour party conference.

In his first interview since the serialisation, he admitted that the book didn't "help" the Labour party currently, but told BBC2's Newsnight: "There's no good time to publish a book like this."

When pressed by anchor Jeremy Paxman on his motivation for publishing it during the conference season, he said he could have caused far more damage.

"I was offfered much more money, a much more lucrative contract to publish this book in April 2015. I was told whatever I was offered by anyone else I could double that to publish it in April 2015 to do maximum damage to the Labour party," said McBride.

"I chose not to do that because I wanted to publish a book at some stage and I thought better to do it now."

He admitted he had received more than £100,000 from the Mail for the book. It is understood the figure he received is close to £130,000.

McBride has admitted that he played a "shameful part" in the feuding between Gordon Brown and Tony Blair which was "hugely destructive" to the last Labour government.

A Tory MP has called on Metropolitan police commissioner Sir Bernard Hogan-Howe to investigate the former spin doctor over the leaking of government information.

McBride admitted that when working for Brown he would sometimes log on to the chancellor's office email system – not his personal email – used for receiving official correspondence and hunt through the folders for cabinet papers or minutes of cabinet meetings.

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