President Lee Myung-bak on Monday urged "pro-North Korea" groups in South Korea to wake up to reality and stop blindly accepting nonsense assertions Pyongyang makes, calling their unconditional following of the communist regime "problematic."

It was the first time Lee, who has tried to avoid ideological remarks, has openly criticized those sympathetic to North Korea by using the word, "jongbuk," which means "blindly following the North." Pro-Pyongyang followers are criticized as jongbuk forces in South Korea.

Lee made the criticism in his biweekly radio address, saying North Korea has made "wild assertions" denying its involvement in attacks on South Korea, including a 1983 terrorist bombing targeted at the then South Korean president in Myanmar and the 2010 sinking of a South Korean warship.

"The North has repeatedly made such wild assertions, but what is more problematic are some pro-North Korea groups within our society," Lee said. "Just as the international community is demanding the North change, those people who unconditionally support North Korea must change; they are, after all, living in the Republic of Korea that has joined the ranks of advanced countries."

Criticism of pro-North Korean groups has risen sharply in South Korea in recent months after some lawmakers-elect of the leftist opposition Unified Progressive Party displayed strong leanings to the communist nation and reluctance to criticize the regime.

Earlier this month, Lee visited Myanmar as the first South Korean president to visit the country in 29 years since the North's

1983 terrorist bombing ripped through a Yangon mausoleum. The attack killed 17 South Koreans, including some Cabinet ministers.

Lee visited the mausoleum during this month's trip.

"What wrong did they do and to whom? They were the victims of the division of the country and a ruthless terrorist attack. I could not hold back my anger thinking about who took their lives. I felt all choked up," he said in the radio address.

Lee praised Myanmar for opening up to the outside world with sweeping democratic reforms, saying he hopes the North will follow in Myanmar's footsteps, "change its thinking, make new friends and open a new age."

South Korea and Myanmar can become good business partners, Lee said.

"It is significant for Korea to have another big market the size of Vietnam in the region," he said. "Our country can be assured of the abundant resources of Myanmar and actually invest in it. If our two nations consult and make thorough preparations this year, Korean businesses can make inroads in earnest, beginning next year." (Yonhap News)