Lee Jae-myung, right, head of the main opposition Democratic Party of Korea, attends a meeting of the party's Supreme Council at its chapter in Chuncheon, the capital of northeastern Gangwon Province, Dec. 23, one day after he was asked to appear before prosecutors next week for questioning over allegations involving a football club years ago. Yonhap

Opposition leader Lee Jae-myung protested strongly Friday after prosecutors asked him to appear for questioning over bribery allegations surrounding corporate donations to a football club.

Lee was asked to come to the Suwon District Prosecutors' Office next week over allegations the city government of Seongnam attracted some 16 billion won ($12 million) in corporate donations to its municipal football club in return for administrative favors.

Lee, who was elected as leader of the Democratic Party of Korea (DPK) this year, served as the mayor of Seongnam, just south of Seoul, when the donations to Seongnam FC were made in the mid-2010s.

The DPK leader denounced the probe as politically motivated and renewed his pledge to fight against it.

"I will confidently confront and prevail at the forefront of the shameless probe aimed at destroying the main opposition," Lee said at the party's Supreme Council meeting in the northeastern city of Chuncheon.