Google and Facebook must take responsibility and remove extremist content on their platforms, WPP CEO Martin Sorrell told CNBC on Friday, but he added that advertisers boycotting video service YouTube "doesn't make sense".
A number of major brands pulled ads from Google-owned YouTube this month after they were appearing next to inappropriate content. AT&T, General Motors and Johnson & Johnson are among the companies who have suspended ads on YouTube.
Sorrell said that there "may be an argument" for temporarily suspending ads on YouTube, but a permanent boycott wasn't a good move.
"Boycotting what is one of the most powerful, if not the most powerful medium, doesn't make sense," Sorrell told CNBC.
Last year, WPP spent $5 billion advertising with Google on behalf of clients, the CEO told CNBC in December, making it the largest digital platform it spends on, compared to $1.7 billion for Facebook and $90 million for Snapchat. Google is likely to make $72.69 billion in ad revenues in 2017, according to eMarketer data.
Sorrell said WPP has partnered with Google to introduce technology to monitor where ads are appearing, but did not give further details and admitted that "you can't make things 100 percent brand safe." The WPP CEO said you can deal with the issues around ad placement effectively but so far there hasn't been a good response.
"With duopolistic control or influence comes responsibility, and last time I checked Google's revenues and margins and Facebook's revenues and margins, they were certainly, I look at them with some degree of envy, it's true ... With authority or position comes a responsibility, and they have got to step up and take responsibility," Sorrell told CNBC.
He added that Google does "deserve credit" as they have reacted to the situation. Extremist content on social platforms was back in focus after the recent London terror attack. On Thursday, Google, Twitter, Facebook and Microsoft met with the U.K.'s Interior Minister Amber Rudd and agreed to create new "technical tools to identify and remove terrorist propaganda". The technology giants also agreed to find ways to remove extremist content faster.
Ongoing debate around the roles of such firms has centered around whether the likes of Google and Facebook should be classed as technology companies or media firms. Sorrell said the latter is a more appropriate description.
"They are media companies, they are not technology companies, they cannot masquerade as technology companies and they are responsible, just like you and everybody else, for the content that goes out on their channel and they have to take responsibility," Sorrell said.