Thubron, who serves as Greater China president as well as Asia-Pacific executive vice-president, has spent 10 years with the agency.
The agency has not announced a replacement for Thubron, who will be setting up his own company to advise brands that want to enter Asia or expand within Asia on strategy and communications. He will remain based in Hong Kong and Australia.
After 26 years in the business, Thubron said a full-time regional role at another agency is not on his career agenda. "The skills that we [ad execs] have, the way that we see the world; these are deemed valuable not just in the physical production of advertising," he told Campaign Asia-Pacific.
Keith Smith, international president of TBWA Group, commented that Thubron will be in a transition period until February 2015, and is leaving on "perfectly amicable" terms. "Ian has contributed significantly to TBWA, particularly in the last five years as president of Greater China. We’ve grown, we’ve won awards, we’ve opened new companies, and we’ve become a top performer within our network. With our team in place, TBWA will continue to thrive in Greater China. We all wish Ian well in his new endeavours."
This story has been updated after its initial publication.