Lord Saatchi has defended his brother Charles over his high-profile divorce from TV chef Nigella Lawson.

Tory peer Maurice Saatchi, 67, said his elder brother was a victim of “persecution mania”.

Mr Saatchi and Ms Lawson, respectively 70 and 53, divorced after the advertising mogul appeared to be grabbing his wife’s throat outside a Mayfair restaurant in June.

Mr Saatchi initially dismissed the incident as a “playful tiff”. Ms Lawson later applied for divorce on grounds of “unreasonable behaviour”.

Lord Saatchi spoke of the public reaction to his brother’s divorce on the Andrew Marr show on BBC1 on Sunday.

He said no one would really know what goes on in a marriage until “somebody installs CCTV in people’s bedrooms – which may be the next step of our surveillance state”.

He went on to say that “persecution mania, love, sex, marriage and work” were among factors that “produce great difficulties in people. Family and marriage is certainly one of the most complex areas” .

The brothers, born to Iraqi Jewish parents, co-established the Saatchi & Saatchi firm over 40 years ago. It remains one of the most famous names in advertising.