Jennings had managed the corporate reputation and public affairs of clients including the World Health Organization, CME Group, Northern Trust and Emerson. He had also assumed the duties of Jin Lu, managing partner of Beijing, when he departed in August.
Kushner was a managing partner for Japan.
Kushner said the move will allow Jennings to focus on clients rather than administrative duties.
In addition, Robyn Joseph, formerly partner and head of public affairs for Hong Kong for four and a half years, has also been named a senior advisor.
In Beijing, Tracy Hu has been promoted from partner to managing partner and John Zhao, an associate director for 12 months, is now director.
In Hong Kong, Caroline Briggert, associate director in Hong Kong for 11 months, and Sophie Sophaon, a director in Hong Kong for nine months, are now co-managing partners.
"This is an executive decision made at the headquarters level, and it is a good time for the restructure now," Kushner said. All the changes at the firm took place on 3 November.