The anti-Muslim atheist was due to speak at event hosted by KPFA Radio in Berkeley, California next month.
Organisers said that Dawkins had made “abusive speech against Islam” when cancelling his event, but he argued that his criticisms were not directed at Islam.
The disgruntled professor has called on KPFA Radio to review his past statements and apologise.
In a letter addressing ticket-holders, the radio station wrote: “We had booked this event based entirely on his excellent new book on science, when we didn’t know he had offended and hurt – in his tweets and other comments on Islam, so many people.”
The letter which Dawkins published online added that it does not support “hurtful” or “abusive speech”.
It also included an apology “for not having had broader knowledge of Dawkins views much earlier”.
Local media outlets have reported that Bay Area residents had raised concerns about statements made by Dawkins in his anti-religion book “The God Delusion”, including a tweet he posted in 2013 saying “Islam is the greatest force for evil in the world today”.
In response to the organisers, Dawkins wrote in an open letter that he “never used abusive speech against Islam”.
He said critical statements he made in the past were directed at “Islamism” – allegedly referring to Muslims who use Islam for political objectives.
Dawkins also pointed out that he is a regular “critic of Christianity but have never been de-platformed for that”.