SEOUL, South Korea — Prime Minister Lee Wan-koo of South Korea said Tuesday that he had offered to resign over a snowballing bribery scandal, dealing a blow to President Park Geun-hye, whose government has already been rocked by a ferry disaster.
Mr. Lee has been under mounting pressure from within Ms. Park’s governing Saenuri Party, as well as from the opposition, to step down after an allegation emerged this month that he took 30 million won, or $27,700, in illegal cash donations from a South Korean businessman in 2013.
The businessman, Sung Wan-jong, hanged himself from a tree on April 9, the day he was scheduled to appear before a court to fight attempts by prosecutors to arrest him on corruption charges. He was the first target in the Park government’s widening investigation into corruption allegations that were said to have taken place under her predecessor, Lee Myung-bak.
Yet Mr. Sung, a former lawmaker and chairman of a bankrupt construction company, did not go silently: He left behind a memorandum and a tape of a telephone interview that he gave to a South Korean newspaper hours before he died. On the tape and in the memo he detailed illegal cash gifts that he said he had given to Mr. Lee and a few other key political allies of Ms. Park, including both of her former chiefs of staff.