An application to run the event at Hyde Park or Greenwich Park has now also been refused, with an official writing to say: ‘We do not permit any religious observances in the Royal Parks, either in their own right or as part of a demonstration.’

Bible Society chief executive James Catford accused the Royal Parks of discrimination, saying: ‘At Bible Society, we never seek to impose the Bible on anyone. Our mission is about inviting everyone to experience scripture and consider it thoughtfully – we offer the Bible to the world.

‘Telling the story of Jonah to children, inside a giant inflatable whale, is intended to be a free, fun event over the summer. The Bible is packed full with some of the greatest stories ever told. We believe that every child is entitled to encounter the Bible. It’s a matter of justice.’

We believe that every child is entitled to encounter the Bible

He added: ‘We can’t see that there’s any reasonable basis for Royal Parks to discriminate against us in this way.’

An alternative venue is needed for three days and three nights in August, either in London or close to Swindon.

Head of media Rachel Rounds said: ‘It’s been really hard to find a venue to host the whale over the summer. It would be great to find a home for our whale with the help of Bible Society supporters.’