South Korea, Vietnam, sign business deals SEOUL, March 29 (UPI) -- The prime ministers of Vietnam and South Korea have signed agreements to increase commercial and industrial cooperation. Vietnamese Prime Minister Nguyen Tan Dung met with Prime Minister Kim Hwangsik after the two-day Nuclear Security Summit in Seoul, the Yonhap News Agency reported Thursday. The prime ministers signed deals covering solar energy and waste treatment projects in Vietnam. Dung also met with South Korean President Lee Myung-bak to discuss trade, nuclear power and infrastructure projects, the news agency said.