Speaking to CNBC, Sorrel, however, added that advertisers opting to boycott video service provider YouTube does not make sense.
Several major brands including General Motors pulled adverts from Google-owned YouTube this month after they appeared next to inappropriate content.
Sorrell said that while there may be "an argument" for companies to temporarily suspend ads on YouTube, a permanent boycott would not be a good move.
"Boycotting what is one of the most powerful, if not the most powerful media, doesn't make sense," Sorrell said.
According to the CEO, WPP shelled out $5 billion advertising with Google last year on behalf of clients, compared with $1.7 billion for Facebook and $90 million for Snapchat. This revenue made Google the largest digital platform it spends on.
According to eMarketer data, Google could potentially make $72.69 billion in ad revenues this year.
Sorrell revealed that WPP has partnered with Google to introduce technology that will monitor where ads are appearing.
He, however, refused to reveal further details on the initiative, though he did admit that "You can't make things 100 percent brand safe."
Sorrell said that you could deal with the issues on ad placement effectively, but so far the response has not been encouraging.
He said that Google deserves credit as they have reacted swiftly to the situation.
The recent London terror attack brought back in focus extremist content on social media platforms, with Google, Twitter, Facebook and Microsoft meeting on Thursday with the UK's Interior Minister, Amber Rudd.
The meeting agreed to create new "technical tools to identify and remove terrorist propaganda."