(AGI) Seoul, June 30 - North Korea is to try two Americans oncharges of having performed "hostile actions" against thestate. It holds three U.S. citizens in custody. Meanwhile,Pyongyang proposed a ceasefire with South Korea this week. Itmade the proposal on the eve of a visit to Seoul by ChinesePresident Xi Jinping, the biggest ally of the communist regimeof North Korea. . .