Korean American professor Morse Tan, center, visits a polling station in Pyeongtaek, Gyeonggi Province, where early voting for the June 3 local elections was under way, Friday. Yonhap

A Seoul court on Thursday rejected a request for a suspension of an exit ban against Morse Tan, a Korean American scholar accused of defaming President Lee Jae Myung, legal sources said.

The Seoul Administrative Court rejected Tan's request to suspend the exit ban, which the justice ministry imposed earlier this week, saying that a potential suspension could have a serious impact on the public interest, according to the sources.

Tan is suspected of having defamed Lee by spreading false information about him, claiming during a Washington event last year that Lee had been involved in a murder case during his youth, and that he was sent to a juvenile detention center.

The U.S. scholar, affiliated with the U.S.-based Liberty University, is also known for making claims of election fraud in Korea, including his earlier argument that the last presidential election here was rigged.