An advisor to former U.N. Secretary-General Ban Ki-moon, a potential presidential contender, on Tuesday offered a glimpse into his economic policy that aims to upgrade South Korea's capitalism model blamed for economic polarization.

   Speaking to Yonhap News Agency, Kwak Seung-jun, an economics professor at Korea University, put forward three key words to outline Ban's economic policy: "warm" market economy, upgraded capitalism and institutions in line with global standards.

   Kwak has been cited as part of Ban's preliminary campaign team consisting of his close aides such as former South Korean Ambassador to the U.N. Kim Sook. The team has reportedly been discussing how to support Ban's political activities to boost his presidential prospects.

   Ban, who is set to return home on Thursday after his 10-year term as U.N. chief, has yet to clearly declare his presidential bid. But he has said he would "give my all" if it would help advance his home country, the strongest signal that he would throw his hat into the ring.

   Kwak, in particular, stressed the need for South Korea's economy to pursue a new model of capitalism that ensures the voluntary redistribution of wealth within the ever-growing private sector and break away from the "old" system that created various problems such as social and economic polarization.

   "The core of capitalism is evolving, and we cannot just stay within the old system," he said.

   Kwak also indicated his support for a tax increase on the wealthy.

   He, in particular, mentioned the Buffett Rule, a tax plan Hillary Clinton backed during her unsuccessful presidential campaign last year. The rule stipulates that any taxpayer making more than $1 million per year must pay a minimum federal tax rate of 30 percent.

   Asked if Ban's campaign is considering an increase in corporate taxes, the professor said, "An overhaul of the taxation system will be a very crucial part. (The overhaul) will cover the entirety of corporate taxes and income taxes."

   Kwak added that rather than the government seeking to artificially modify tax rates, Ban's administration, if elected, would promote the role of the private sector to enhance the tax system.

   "In this way, private firms can survive. Otherwise, (the government) can be seen as an enemy of the citizens, as we have seen in the candlelight vigils (against the current government)," he said. (Yonhap)