The true extent of the vicious internal feuding within the faction-riven new Labour government has been laid bare on the eve of the Labour Party conference.

Once close political allies, the relationship between former prime ministers Tony Blair and Gordon Brown grew increasingly acrimonious during the party's time in power, spilling over into open bitterness and hostility.

In extracts from a new memoir, published in the Daily Mail, Mr Brown's disgraced former spin doctor Damian McBride describes how he launched smear campaigns against Cabinet ministers during his boss's leadership bid.