Concern is growing for ex-McLaren boss Martin Whitmarsh following reports that he ‘just can’t stop laughing’.

Friends of the former team principal say the ‘uncontrollable mirth’ began around 15 March and has been coming and going in waves ever since, subsiding to a ‘general chuckle’ in the week and peaking at ‘full blown howls of derisive laughter’ which typically happen ‘every other Sunday or so’.

Doctors say they are yet to find the cause of Whitmarsh’s constant and uncontrollable laughter. ‘We have asked him if it relates to something in his past,’ admitted one medic. ‘But that just seems to make him laugh harder’.

Whitmarsh himself is said to be incapable of explaining what is making him laugh for so long and with such glee, only getting as far as an ‘M’ sound before exploding into fits of giggles.

‘We are no closer to finding out why he’s been so amused since the early hours of a Sunday morning in March,’ admitted one senior doctor. ‘Although I have just spoken to a colleague in Woking who reports seeing a mild version of the same condition suffered by a Mr Magnussen.’