The illustrator behind the popular children's book, The Gruffalo, says the bestseller would not exist if the UK was outside the European Union. Born in Germany, Axel Scheffler had come to the UK in 1982 when he studied illustration at the Bath Academy of Arts.

"Without British membership in the EU, millions of British children would have grown up without The Gruffalo, Room on the Broom's witch, and Stickman - at least in their existing form," Scheffler wrote in a blog. "The Gruffalo and all the other books I've illustrated would not have contributed to the British economy, creating jobs and revenue."

Gruffalo, which has sold nearly 13 million copies worldwide, was a collaboration between Scheffler and children's author Julia Donaldson. "Just unravelling the story of one 'British product', The Gruffalo, shows that Britain's engagement with Europe is not simply a political issue, but an economic and cultural one," said Scheffler, reported Sky News.

"And if anyone had asked me when I arrived in the UK in 1982 that, 34 years later, the UK would be debating whether to stay in the EU, I would have thought they were being ridiculous. And, frankly, I can't quite believe that this referendum is happening."

Scheffler says that he is concerned for the future of his children if the UK were to exit from the EU, since his child will be born in the UK to a German father and a French mother. "I am concerned for my own future in the UK: I have no wish to live outside the European Union. I know that I am just an illustrator, but I felt that, given my experience of being a German who feels at home here in the UK, I have an obligation to speak out, and given the global popularity of the books I have illustrated while I have lived in this country, maybe someone will listen to me.

"An open, united and peaceful Europe enriches us all. We have so much to lose by taking wrong decisions."

The UK Prime Minister David Cameron has announced that a referendum will be held on 23 June to decide if Britain should remain in the European Union.