美国总统特朗普：与韩国代理总统进行了良好的通话，谈到了关税、购买美国液化天然气以及在阿拉斯加的合资管道项目。

Core Points - The conversation between U.S. President Trump and the South Korean acting president focused on tariffs, the purchase of U.S. liquefied natural gas, and a joint pipeline project in Alaska [1] Group 1 - The discussion included topics on tariffs, indicating ongoing trade negotiations between the U.S. and South Korea [1] - The purchase of U.S. liquefied natural gas was highlighted, suggesting potential growth in energy exports from the U.S. to South Korea [1] - The joint pipeline project in Alaska was mentioned, which may involve collaboration between U.S. and South Korean companies in energy infrastructure [1]