South Korean President Lee Jae Myung is preparing for back-to-back summits in Tokyo and Washington.

The summits come on the heels of trade deals between Seoul, Tokyo and Washington that have shielded them from the Trump administration's biggest tariffs. There are fears Trump will demand higher payments for supporting the US troop presence in the country. These concerns come as South Korea and Japan face increasing cooperation between their nuclear adversaries, North Korea and Russia.