The US has abruptly scaled back its annual Ulchi Freedom Shield military exercises with South Korea after President Trump ordered the Pentagon to cut them short, catching Seoul off guard and stoking concern among allies such as Japan and Taiwan who rely on American security guarantees. Trump, who has criticised the drills as "inappropriate and hostile" towards North Korea and unnecessarily costly, is reportedly planning to meet Kim Jong Un later this year, raising fears in Seoul that renewed US-North Korea diplomacy could come at South Korea's expense, particularly given Trump's separate frustration over Seoul's refusal to back US action against Iran.

The exercise, involving 18,000 South Korean troops and forces from 11 other allied nations, was halted with only half its programme completed, and South Korea's foreign minister admitted officials had no advance warning of the decision. Analysts warn Trump's unilateral move has dented confidence in the US alliance, with fears he could further reduce the 27,000 US troops stationed in South Korea or abandon denuclearisation policy. Trump's administration has also complained South Korea's $1bn (£734m) annual troop-hosting contribution is inadequate, that a pledged $350bn investment is delayed, and that it discriminates against US firms — prompting some, including Sejong Institute's Cheong Seong-chang, to argue South Korea should pursue its own nuclear deterrent.