Liberal Democrat leader Sir Ed Davey has been fined for speeding after being caught doing 73mph in a 60mph zone on the M1 motorway.

Details of the case, dealt with under an administrative system called the Single Justice Procedure, were revealed by the Evening Standard newspaper on Wednesday.

Mr Davey wrote a letter of explanation in which he said he had tried to pay a speeding ticket issued by Bedfordshire Police after he was caught speeding on the M1 near Caddington.

In a “genuine oversight”, he inadvertently failed to provide his driving licence details so the matter was brought before magistrates to consider in March.

Single Justice Procedure cases are dealt with via paperwork only, with no in-person court case.

Mr Davey wrote: “I apologise. The only mitigation for failing to provide my licence details was just being super-busy and failing to read the form fully, having already accepted liability and made arrangements for the payment.

“Again, I apologise for that. I would like to add that I am the primary driver in a family of four, with two people who have serious mobility issues.

“My son has a lifelong undiagnosed disability which means he cannot walk – we use a Motability vehicle for him.

“My wife has MS, and walks very slowly with a stick, though she can drive as necessary. Thank you for any mitigation you feel able to show in my case.”

He was handed a £72 (€84) fine at Luton Magistrates’ Court, with a £28 victim surcharge, and had three points added to his licence, court staff confirmed.

He was not asked to pay prosecution costs.

A Lib Dem spokesman said: “Ed inadvertently broke the speed limit on the M1, which he is sorry for.

“He has paid the fine and accepted the points on his licence.”