Chung Jin-kyu, an official at the ministry's Overseas Koreans and Consular Affairs Bureau, met with the deputy head of the Taipei Mission and demanded that Taiwan punish the taxi driver and ensure that similar accidents do not recur. It was not immediately clear how the deputy head reacted.
The meeting occurred at a third location, not at the foreign ministry, at the request of the Taipei Mission, the ministry said.
The taxi driver, identified only by his surname Chan, allegedly sexually assaulted the South Koreans in Taipei earlier this month by rendering them unconscious with a drugged soft drink. A blood test confirmed that the victims had sleep-inducing drugs in their blood.
South Korea severed diplomatic relations with Taiwan in 1992 when Seoul established relations with China. China considers Taiwan a renegade province that should be reunified with the mainland.
Taiwan is one of the most popular travel destinations among South Koreans. Last year, more than 800,000 people visited the country, up by 33 percent from a previous year. (Yonhap)