Seoul is to conclude a big arms deal with Washington to gun up against the background of North Korea’s war preparations. US President Donald Trump has agreed with South Korean President Moon Jae-in to revise a joint treaty capping the development of the South's ballistic missiles. Seoul wants to increase the payload on its missiles so it can do more damage. South Korea's development of its ballistic missiles is limited to a range of 800 km (500 miles) and payload weight of 500 kg (1,100 pounds) under a bilateral treaty revised in 2012.
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