Controversial TV presenter Piers Morgan has taken to Twitter to launch a scathing attack at J.K. Rowling’s hugely-successful works on the day she marks 20 years since the first Harry Potter book was published.

The Good Morning Britain host described the series as “execrable literary hogwartwash.”

Morgan was responding to a tweet Rowling posted this morning in which she wrote: “20 years ago today a world that I had lived in alone was suddenly open to others. It’s been wonderful. Thank you.”

Morgan responded: “20 years of conning the easily mesmerised masses with execrable literary hogwartwash. Congrats.” He accompanied his message with a sick emoji face along with a thumbs-down image.

Harry Potter And The Philosopher’s Stone was first published on June 26, 1997 and has since sold more than 450 million copies worldwide having been translated into 79 languages.

Naturally, some well-known faces in the Twitterverse rushed to call the former Daily Mirror editor out.

READ MORE: J.K. Rowling goes on epic 14-tweet-long rant at man who called Theresa May a ‘w***e’

Celebrity MasterChef winner Emma Kennedy hit back: “What a mean thing to say,” while radio presenter Julia Hartley-Brewer‏ added: “You are SO wrong, Piers. The Harry Potter books are wonderful.”

Piers’ tweet came right before he donned a pair of Harry Potter-style glasses and held a wand on the breakfast TV show this morning.

Sitting next to a slightly embarrassed Susanna Reid, he then went on to describe the book series as “badly written tosh.”