Prime Minister David Cameron's latest jibe against Labour's Ed Balls has landed him in hot water with disability campaigners.

The prime minister was forced to apologise after he told the Sunday Telegraph that dealing with the shadow chancellor -- who regularly barracks Cameron in parliament -- was like having someone with Tourette's permanently sitting opposite you.

Tourette Syndrome is an inherited neurological condition which manifests itself with tics, involuntary and uncontrollable sounds and movements.

I was speaking off the cuff, and if I offended anyone of course I am very sorry about that. That wasn't my intention at all, Cameron told BBC television on Sunday.

But I think probably it's a lesson for me that in the Commons I have to try and tune out the noise that's coming and just concentrate on trying to answer the question.

It's not the first time Cameron has referred to Balls' interruptions and mannerisms in his weekly question time sessions in the chamber.

During prime minister's questions early last year Cameron described Balls as one of the most annoying people in modern politics.

Cameron told the Sunday Telegraph: He (Balls) just annoys me.

But I'm very bad, in the House of Commons, at not getting distracted, and the endless, ceaseless banter, it's like having someone with Tourette's permanently sitting opposite you.

His latest jibe at Balls drew a rebuke from campaigner Nicky Clark, whose daughter has Tourette Syndrome.

She told BBC television his comment displayed an utter disregard for the condition and a lack of understanding from our prime minister.

Cameron has experience of caring for a severely disabled child. His oldest child, Ivan, who suffered from cerebral palsy and severe epilepsy, died in February 2009 at age six.

(Reporting by Avril Ormsby)