Cindy Gallop has used a speech in London yesterday – coincidentally on International Women’s Day – to deliver a serve to the world’s biggest media company, WPP, and its lack of gender equality.

Speaking at The Guardian Changing Media Summit, Gallop picked-up on WPP’s own findings that one of its top London agencies, J Walter Thompson UK Group, typically paid its male staff significantly more.

Gallop, whose comments were reported on UK industry site Campaign, also slammed WPP management over Gustavo Martinez, the former JWT global CEO, who is currently facing allegations of sexual harassment and discrimination by a senior JWT staffer.

Martinez, Gallop said, was being paid “a large amount of money to hold a public leadership role” despite the unresolved allegations, and that showed “this is not an industry that says we welcome and we respect women. It’s the complete opposite,” she said.

Interestingly, WPP supremo Sir Martin Sorrell had spoken at the conference only hours before Gallop’s stinging rebuke.

When asked about WPP’s pay disparity, Sorrell said: “We all know the reasons behind it and it’s wrong and has to be fixed.

“Our top quartile is one-third women. The answer therefore is to promote more women. And this will be achieved by encouraging people through qualitative means, quantitative means, quotas, training programmes and bias training – we’re doing all these things,” he added.

According to Campaign’s reporting, Sorrell sidestepped questions about sexism at WPP and the industry in general. Instead, he said he believed that women were more effective employees.

“They have better EQ, organise their time better… women take on more responsibility than men and have more to do than men so they spend less time on watercooler talk,” he said.