The sniping war between WPP and its former owner, Sir Martin Sorrell, has flared-up once again with a senior WPP executive telling Sorrell to “mind his own business”.

CEO of the WPP-owned The & Partnership Group, Johnny Hornby (main photo), has again used a newspaper interview to warn Sorrell to stop talking down WPP and its new CEO, Mark Read.

Hornby – who has publicly chastised Sorrell previously – told the UK’s Evening Standard: “Martin needs to literally mind his own business. He is clever and talented but his constant carping about Mark Read and [chief operating officer] Andrew Scott is verging on unacceptable.”

Sorrell has not yet returned serve on Hornby’s comments.

Previously, Hornby had said Sorrell’s constant sniping was “disrespectful” and made him “look small”.

There has also been reports that the two had repeatedly clashed when Sorrell was CEO of WPP.

In December, Hornby said: “When he [Sorrell] left in the summer the company badly needed a change of direction and strategy that Martin had not delivered and he should allow Mark to get on now unhindered.”

Interestingly, as a pall of doom and gloom descends on many of the large international holding companies, most noticeably Publicis that suffered a 15 per cent drop in its share price last Friday, Hornby’s The & Partnership Group has been an otherwise shining light.

The Evening Standard has reported that its revenues in 2018 were up 33.9 per cent to  £602 million and its pre-tax profits grew 54 per cent to £12.3 million. Hornby attributed the agency’s success to placing 70 per cent of its workforce in clients’ offices to speed up procedures and improve efficiencies.

Hornby said: “More and more large international organisations are needing to be more digital, more agile and have effectively a ‘marketing newsroom’ in-house.”

On the woes of many of the big holding companies, Hornby said: “What Publicis and the other big holding companies are trying to do is turn around large, siloed organisations. It’s like trying to turn around a super-tanker.”