Explaining her decision, Sayer said an increasing amount of her time was being spent working on the integration of Interpublic Group's four communications agencies in Asia, under the Constituency Management Group (CMG) banner.
Sayer said she was also concerned about the integration of the two PR agencies (Golin/Harris and Weber Shandwick) under the CMG banner, because of the strong identities both agencies have historically possessed in the region.
"The big challenge for CMG is to not diminish their brand identities and culture and to ensure client servicing is high," she said.
Weber Shandwick Asia-Pacific president Andrew Pirie refuted the notion that brand identities had been compromised.
"Our whole goal in this process is to maintain and advance the vitality and integrity of both brands," he said. "If we wanted to merge the two brands together we would have done it."
Pirie confirmed that no replacement would be sought for Sayer "at this point in time".
Sayer professed herself "disappointed and surprised that there will be no replacement for my role."