The spin doctor responsible for the famous "Labour isn't working" poster during Margaret Thatcher's general election campaign has died aged 77.

Lord Bell was surrounded by his family when he died following a "prolonged illness", said close friend and business partner Piers Pottinger.

The poster was regarded as having made a key contribution to Mrs Thatcher's general election triumph in 1979.

He was awarded a knighthood by Mrs Thatcher and a peerage by Tony Blair.

Image caption The poster that helped Margaret Thatcher win her first election campaign

The poster, showing a snaking queue of unemployed people, is said to have changed political advertising in the UK.

Lord Bell co-founded the public relations firm Bell Pottinger, which went into administration in 2017.

Mr Pottinger described Lord Bell as a "pioneer in political communication".

"He was a devoted family man and passionate supporter of the Conservative Party, most famously helping Margaret Thatcher win three general elections," he added.

"He was an inspiration to everyone who worked with him. Most importantly to me, he was always a true and loyal friend. Nobody can replace him."