Although Ban, a former foreign minister, has not clearly declared his intention to join the presidential race, his name has long been bandied about as an odds-on presidential contender on the ruling party ticket. Observers here anticipate that Ban will begin political activities after the end of his second five-year term as UN helmsman at the end of this year.

"I have been musing about how and where I will dedicate myself," he said. "I will determine (whether to run for the presidency) after I meet citizens from various walks of life and listen to their opinions. What is most important is citizens' thoughts."

During the interview, Ban made an unusual criticism of South Korea's establishment political parties long plagued by factional feuds and partisan wrangling, but he did not rule out the possibility of his future tie-up with a political bodies.

"You can't do politics all by yourself," he said. "There should be some sort of means and a vision."

Commenting on the political scandal that has threatened to end President Park Geun-hye's presidency, Ban pointed out that citizens are frustrated and enraged by the "lack of good governance," and that the fault lies with the "system and leadership."

"The genuine leadership... genuinely inclusive leadership comes from harmony, integration, inclusive dialogue, national cohesion and social integration. That is what I have usually thought of as the crux of the leadership," he said.

Mentioning the massive anti-Park candlelight vigils that have taken place across the country over the past two months, he said that he felt saddened and heavy-hearted.

"As those deep-rooted evils have been brought to the fore, we should get together and fix them," he said.

Asked if he has given any thought to use his title as a former UN chief on the international stage, rather than in domestic politics, Ban said that at the current juncture, it is "more urgent" for him to work for his own country and fellow citizens.

"It is not like I can't carry out any international task while engaging in domestic affairs. I can handle both," he said.

As for the date of his return to South Korea, Ban reiterated that he would return to Korea in mid-January.

Upon his return home, he will first pay a courtesy call to Acting President and Prime Minister Hwang Kyo-ahn and meet with other national leaders including National Assembly Speaker Chung Sye-kyun, the outgoing UN chief said.

During the interview, the UN chief criticized North Korea as the "most irresponsible" country among the 193 UN member states.

He also expressed concerns about Pyongyang's evolving nuclear and missile technologies, which he said would pose a "hard-to-handle" security challenge at some point.

Following Ban's apparent show of presidential ambitions, the main opposition Democratic Party renewed its stance against his run for the presidency.

"It is undesirable for the UN secretary-general to snoop around the murky domestic political arena," Choo Mi-ae, the party's leader, told reporters.

The minor opposition People's Party, however, showed its interest in inviting him into its party's primary race.

"I think he can join us," said Kim Dong-cheol, the interim leader of the party. (Yonhap)