Notional red lines are entirely ineffective as a peacekeeping tool, a nightclub owner said from the wreckage of his property today.

Ray Doyle decided to save money on bouncers after noting how the US and Russia simply warned against ‘crossing red lines’ to avoid open conflict, and now faces closure after a single devastating night.

Mr Doyle said: “The club’s red line was no violence and problems arose when a group of customers established their own red line as extreme violence.

“I said to one ‘You’re crossing a red line’ and he said ‘How about I draw some red lines on your face?’

“So I said ‘The whole system relies on people not unilaterally drawing irreconcilable red lines.’

“Then I woke up in hospital with these red lines on my face.

“Rather than keep the peace, I think red lines may be the reason my nightclub looks like the OK Corral.”

Mr Doyle’s warning comes after Kim Yong Un conducted tests of a red pen in breach of a UN resolution.

A spokesman for the North Korean supreme leader said: “That resolution is going to be so far over this red line once drawn.”