South Korean President Lee Myung-bak and Swedish King Carl XVI Gustaf agreed Wednesday to expand all-round cooperation between the two countries, especially in science and green growth, the presidential office said. King Gustaf and Queen Silvia arrived in Seoul Tuesday on a four-day visit that also includes tours to the truce village of Panmunjom on the border with North Korea and to the World Expo under way in the southern port city of Yeosu, South Korea\'s news agency (Yonhap) reported. The King visited South Korea five times before, but this week\'s trip was his first state visit. In Wednesday\'s meeting, Lee expressed his appreciation for Sweden\'s role in peace and stability on the Korean Peninsula, such as its dispatch of medical teams during the 1950-53 Korean War and its participation in the Neutral Nations Supervisory Commission overseeing the armistice that ended the conflict. Sweden was also a member of an international team that investigated the mysterious sinking of a South Korean warship in waters near the tense sea border with North Korea in 2010. The investigation concluded that the North torpedoed the warship Cheonan. King Gustaf noted that South Korea has achieved rapid economic growth and has made contributions to security and prosperity of the international community, such as its hosting of a G20 summit in 2010 and this year\'s Nuclear Security Summit. He also wished South Korea a successful hosting of the Yeosu Expo, the office said. The two leaders said that trade and investment between the two countries have steadily expanded and cooperation between science research institutions of the two sides has been brisk. They agreed to further boost cooperation in basic science and green growth, the office said. Trade volume between South Korea and Sweden has increased from US$1.64 billion in 2009 to $2.05 billion in 2010 and to $3.19 billion last year. The two countries forged diplomatic relations in 1959.