I suppose it had to happen eventually. A Northern Ireland bakery run by devout Christians is in trouble after refusing a request to make a gay-themed cake depicting two puppets, the Sesame Street couple, Bert and Ernie.

We are all accustomed by now to newspaper stories about Christian owners of bed and breakfast establishments being prosecuted for not allowing gay couples to have a room for the night but gay cakes is something else.

Given that Northern Ireland is the only part of the UK where gay marriage is not legal the refusal is particularly controversial.

And, according to The Guardian, the issue is complicated even further because Northern Ireland has its first openly gay mayor, Andrew Muir, who has inevitably backed the legal action.

As someone once said you couldn’t make it up. You really couldn’t.