 In 2003, Thiam joined the Rally of the Republicans and began to oppose President Laurent Gbagbo.In 2010, he was the head of Alassane Ouattara's campaign for president in the Yamoussoukro area.In 2011, after Ouattara had won the election and succeeded Gbagbo, Thiam was appointed governor of the Yamoussoukro Autonomous District and was made member of the national cabinet.