South Korea and the United States have shortened their annual joint military exercises and reduced field training after President Donald Trump ordered a “substantial reduction” in the drills.

The Ulchi Freedom Shield exercise, which began on August 17, will now run for five days instead of the originally planned 11, ending on August 21, South Korea’s Joint Chiefs of Staff said.

The JCS said the shortened schedule was agreed upon following a request from Washington, with some combined field manoeuvres also being scaled back.

South Korean media reported that Defence Minister Ahn Gyu-back said the allies were moving to cancel the second phase of the exercises, which was expected to focus on counterattack operations following an initial defensive phase.

A U.S. Department of Defense official confirmed that the exercise and related live-training activities had been substantially reduced, with some events cancelled and others converted into simulations.

Despite the changes, the official said the revised exercises would maintain essential military readiness and meet U.S. training objectives.

The move follows Trump’s announcement Sunday that he had ordered a reduction in the exercises, citing his “very good relationship” with North Korean leader Kim Jong Un.

Trump has argued that large-scale U.S.-South Korean military exercises send an unnecessarily hostile signal to Pyongyang. He also linked his decision to Seoul’s refusal to participate in the U.S. and Israeli war against Iran.

South Korean Foreign Minister Cho Hyun told lawmakers Wednesday that officials in Seoul and Washington had not received advance notice of Trump’s decision to scale back the exercises.

The development marks a significant adjustment to one of the key annual military exercises underpinning the U.S.-South Korea security alliance, as Washington seeks to balance military readiness with efforts to reduce tensions on the Korean Peninsula.