SEOUL (AFP) - South Korean president-elect Park Geun Hye stressed the need for "clean government" today, the day after her nominee for prime minister embarrassingly withdrew ahead of his confirmation hearings.

Kim Yong Joon, 74, a former Constitutional Court chief and current head of Park's transition committee, stepped aside after media reports raised suspicions about his accumulated family wealth.

Allegations were made that he had benefited from a series of unethical real-estate deals in the 1970s and 80s, while other questions were raised over the exemptions his two sons received from South Korea's mandatory military service.

"I decided to resign as the prime minister nominee as I have caused concerns to the people and trouble to the president-elect," Kim said in a statement yesterday.

His withdrawal is a major embarrassment for Park, who has spent the past few days berating outgoing President Lee Myung Bak over his decision to pardon a number of friends and close aides serving jail terms for corruption.

Successive South Korean presidents have taken office vowing to combat official graft only to be tainted by corruption scandals involving relatives or senior members of their administrations.

In a policy meeting with her transition team today, Park said she was determined that her promise of "clean and competent government" would be more than just rhetoric.

"Even if there is a litre of clean water, we cannot drink it if a drop of waste goes into it," Park was quoted as saying by the Yonhap news agency.

"Likewise, even if 99 per cent of public servants are clean, the people will distrust the whole public service if one per cent commit corruption and irregularities," she added, without specifically mentioning Kim's case.

Kim, who overcame polio to become the country's youngest judge and went on to a seat on the Supreme Court and finally to head the Constitutional Court, had been a surprise nominee.