He is also said to claim Sir Fred “deserved to be a pariah” when he later refused to slash his pension after being fired by the RBS board.
A Labour-supporting website has published details of what it claims are the contents of Mr Darling’s new book, Back from the Brink – 1000 Days at Number 11, which is due out next week.
Writing about the bankers and the 2008 crash, Mr Darling is said to comment: “My worry was that they were so arrogant and stupid that they might bring us all down.”
The Edinburgh South-West MP reportedly says former HBOS chief executive Andy Hornby “looked like he was about to explode” when confronted with the magnitude of what had happened on his watch.
And he is said to complain that all the bank bosses showed an arrogance and a lack of gratitude for the massive, multi-billion-pound taxpayer bailout.
Mr Darling is also said to describe former Prime Minister Gordon Brown’s mood as he sought to tackle the financial crisis as “brutal and volcanic”.
The blog, Labour Uncut, says Mr Darling singles out Ed Balls and Shriti Vadhera as key Brown lieutenants running what amounted to a shadow treasury operation within the government.
Baroness Vadhera is reportedly described as “only happy if there was blood on the floor – preferably of her colleagues”.
Mr Darling is quoted saying Bank of England governor Sir Mervyn King was “amazingly stubborn and exasperating”.
The book is said to reveal how Mr Brown sought to run what Mr Darling describes as a shadow treasury within No 10, undermining the real Treasury next door. It is said Mr Brown even tried to put his own aides in the Treasury to report back to him on.
Mr Darling is understood to have refused to have the newly ennobled Baroness Vadhera in his team, and when Brown ally Yvette Cooper was appointed Chief Secretary to the Treasury in January 2008, he concluded she was there to “keep an eye” on him.
Mr Darling was made Chancellor by Mr Brown in July 2007, as one of his most trusted allies. However, the relationship is said to have soured after Mr Darling warned in an interview that the economic times the country was facing were “arguably the worst they’ve been in 60 years”.
The book is understood to confirm Mr Brown later tried to replace him with Ed Balls, a move thwarted when Mr Darling threatened to walk out.