Former WPP CEO Martin Sorrell should have done more to promote creative inspiration during his reign over the advertising industry, a top executive told CNBC Monday.

Speaking on the sidelines of Cannes Lion festival, Ami Hasan, chairman at Art Directors Club of Europe (ADCE), told CNBC that Sorrell and other global leaders of the advertising industry had missed an opportunity to promote creativity over the last decade.

“The era of Martin Sorrell dominating the business … has not been that glorious because he mostly talks to investors and he mostly talks about money and his stock price and what the industry needs is a couple of figureheads that would speak about creativity,” Hasan said.

“For us, for those that do the ads, it is extremely inspiring to hear these titans speak about creativity and unfortunately Martin Sorrell hardly ever does that,” he added.

Martin Sorrell was not immediately available to comment when contacted by CNBC.

After more than 30 years in charge of the world’s biggest marketing and advertising group, Martin Sorrell resigned as chief executive of WPP amid allegations of serious personal misconduct — which he has denied.

Sorrell also strenuously denied company money was used to pay for a prostitute, following an investigation into a whistleblower’s allegations.

The ad titan turned what was effectively a wire shopping basket company into a global advertising group worth around $20 billion.

However, following his resignation at the end of May, Sorrell has since unveiled plans for S4 Capital — his new venture in the ad industry. The group has reportedly received non-binding support for around $200 million of further funds to help launch acquisitions.

When asked whether he expected Sorrell to create another WPP with his next project, Hasan replied: “He is highly connected, he has the financial backing and he is a smart guy so he can do it but if I was 73 then I would not bother.”

Sorrell is expected to attend the annual gathering of the advertising industry in France this week.