We face a number of outstanding problems in relations between the two Koreas and the question of the North Korean nuclear program, which has become an international problem, Woon-ki said after meeting Mesic.
The South Korean official called on President Mesic to support efforts to solve those outstanding issues in a peaceful way, which Mesic pledged to do.
"We will do all we can in bilateral relations and help as much as we can," he stated.
The two officials discussed economic relations between Croatia and South Korea, notably in tourism.
President Mesic said he wanted South Korea to invest capital in Croatia's tourist accommodation facilities and invited Koreans to visit the Adriatic Sea.
Woon-ki said that Koreans felt great attachment to the Croat people, thanks, among other things, to the reputation of several Croatian athletes in South Korea.
Later in the day, President Mesic will meet for the second time with Korean President Rooh Moo-hyun, who will give a dinner in his honour.
On Friday, President Mesic will hold talks in Seoul, Suwon and Boondang with managers of several leading Korean companies on investment possibilities in Croatia.
During the visit to South Korea, representatives of the Croatian Reconstruction and Development Bank signed an agreement on cooperation with the Korean Export-Import Bank and the Korean Export Insurance Corporation.
Trade between the two countries in 2005 amounted to some USD 186 million, with imports from South Korea making up around 182.4 million and Croatian exports making up 4.281 million of the amount.