Nutt said cocaine overuse made bankers “overconfident” and caused them to take more risks, leading not only to the most recent crisis, but also the collapse of Barings bank in 1995, the Telegraph reports

He said cocaine was part of the City’s “culture of excitement and drive”.

The Telegraph quotes him saying: “Bankers use cocaine and got us into this terrible mess. It is a ‘more’ drug”.

Nutt has made many a controversial claim about drugs and was fired as the government’s most senior drug adviser in 2009, after saying there was “not much difference” between the harm caused by horse riding and taking ecstasy.

The then Home Secretary Jacqui Smith requested an apology, but Nutt went on to claim that alcohol and tobacco were more dangerous than some illegal drugs such as LSD, ecstasy and cannabis.

Nutt, currently working as professor of neuropsychopharmacology at Imperial College London, was fired for criticising the moral tone of the government’s drug policy.

He has recently accused the coalition of having “chickened out” of minimum pricing on alcohol, which could help to curb binge drinking.