A book written by Stephane Charbonnier (Charb), former editor of French magazine Charlie Hebdo, is to be published posthumously, according to the BBC.

Entitled An Open Letter to the Fraudsters of Islamophobia who Play into Racists' Hands, the work was finished just two days before the attack on the magazine’s office that resulted in the death of 12 people.

The book is a defence of Charb’s editorial stance and the magazine's controversial depiction of the Prophet Mohammed, upholding the right to ridicule any religion.

‘By what twisted logic is humour less compatible with Islam than with any other religion? … The suggestion that you can laugh at everything, except certain aspects of Islam, because Muslims are much more prickly that the rest of the population – what is that, if not discrimination?,’ writes Charb.

He argues that the battle against racism is being replaced by a misguided struggle against ‘Islamophobia’, and criticises the media for helping popularise the term as ‘any scandal that contains the word “Islam” in its title sells.’

Charb also questions organised religion and its followers who take the Bible or Koran literally.

‘The problem isn’t the Koran, nor the Bible, [two] badly written, incoherent and soporific novels, but the believer who reads the Koran or the Bible like one reads an instruction manual on how to assemble an Ikea shelf.’

Following the attack at the Charlie Hebdo headquarters, the phrase Je suis Charlie was adopted by supporters of free speech across the world. The magazine was granted nearly one million euro by the French government, as well as donations by the Guardian Media Group and the French Press and Pluralism Fund. Demand for the first issue following the attack had the print run increased from 60,000 to five million copies.