Last night, critics claimed the EU was at odds with both science and common sense. Conservative MEP Roger Helmer said: “This is stupidity writ large.

“The euro is burning, the EU is falling apart and yet here they are: highly-paid, highly-pensioned officials worrying about the obvious qualities of water and trying to deny us the right to say what is patently true.

“If ever there were an episode which demonstrates the folly of the great European project then this is it.”