While stopping short of announcing a presidential bid, Ban confirmed he was considering a return to the domestic arena on Thursday.

"Many people have asked me whether I have a will for power. If 'will for power' means uniting a divided country into one and making it a first-class country again, then I have already said I am ready to burn my body in devotion to this and my mind hasn't changed," he said during a televised conference at Incheon International Airport.

The 72-year-old diplomat has completed a 10-year term as the head of the UN, and had previously served as foreign minister in South Korea between 2004 and 2006. He was never affiliated with any of the major parties. Many observers consider him one of the favorites to replace the embattled Park Geun-hye as president and over the massive influence-peddling scandal gripping the nation. His time as the UN general secretary also boosted his popularity among the voters.

On Thursday, Ban said he would discuss his political ambitions before announcing a decision.

"I've been saying I will listen to our people's thoughts after returning home," he said. "I will make a selfless decision with a humble heart. That decision won't take long."

Scandal upon scandal

Ban returns to country shook by the scandal involving both the politicians and big business. On the day of his arrival, a special prosecutors' team was grilling the de facto leader of the South Korean electronics giant Samsung for allegedly bribing president's confidante Choi Soon-sil to gain favor with the state.

Watch video 00:19 South Korea political scandal takes new twist

Parliament has already voted to impeach the 64-year-old Park and the case is currently being examined by South Korea's Constitutional Court.

However, Ban's political ambitions may also suffer a blow by a bribery scandal involving his younger brother and nephew. The two were accused of a scheme to bribe a Middle Eastern official over a sale of a building complex in Vietnam. The case was raised before a federal court in Manhattan. Ban said he was dismayed by the scandal, but insisted he had "absolutely no knowledge" of the scheme.

"My nephew is grown and I barely had any involvement in his life or how he does business," he said, commenting on the case.

dj/sms (dpa, AFP, AP, Reuters)