SEOUL: Donald Trump said he ordered the Pentagon to scale back "inappropriate and hostile" military drills with South Korea, hours before the exercises began on Monday.

The US president cited his "good relationship" with North Korean leader Kim Jong Un in his latest rebuke to long-standing alliances with Western partners.

South Korean officials said the exercises had begun as planned and that they hoped the personal chemistry between Trump and Kim would bring them back to talks.

North Korea has not responded publicly, though it has previously voiced anger at the regular joint manoeuvres, which take place in the South.

The drills began as American allies in East Asia fret over North Korean displays of weapons capabilities and its growing alignment with Russia as well as traditional backer China.

"Based on my very good relationship with Kim Jong Un, of North Korea, I am not happy with the fact that the United States has, long ago, agreed to participate in Joint Military Exercises with South Korea," Trump wrote on his Truth Social platform.

"These exercises are not only costly, with much of these costs paid for by the United States of America (as usual!), but send a signal that is totally inappropriate and hostile, to a Country that, as long as Donald J. Trump has been President, has been unthreatening and respectful," he added.

He took direct aim at South Korea, writing: "I recently asked the President of South Korea if they would like to join us in the Denuclearization of the Islamic Republic of Iran, and they said, 'No thanks!'"

As it was too late to cancel the drills, Trump said he had ordered Defence Secretary Pete Hegseth to "substantially reduce" them.

The 11-day Ulchi Freedom Shield exercises are designed to prepare for a possible war with North Korea.

Colonel Ryan Donald, spokesman for the US and South Korean Combined Forces Command, has said they will simulate combat against North Korean troops steeled by their deployment on Russia's side in its invasion of Ukraine.

The manoeuvres kicked off as "previously notified and scheduled", South Korea's defence ministry said.

Seoul's presidential office told AFP it remained in "close coordination" with Washington over the exercises.

The office "hopes that the friendly relationship between the leaders of the United States and North Korea will lead to meaningful dialogue".

Anxiety in Asia

Pyongyang decries the drills as dress rehearsals for an invasion.

It recently test-fired a ballistic missile over the Sea of Japan, and warned on Friday it could respond to the exercises with a "new level of deterrent".

The US stations about 28,500 troops in South Korea to bolster the country's defences, a legacy of the 1950-53 Korean War that ended with an armistice rather than a peace treaty.

But Trump's repeated criticism of time-honoured alliances has cast doubt on American commitments to security in East Asia.

Asked if China supported new dialogue between the United States and North Korea, Beijing's foreign ministry said on Monday it had "noted the relevant reports".

"Maintaining peace and stability on the Korean Peninsula and promoting the political settlement of the peninsular issue are in the common interests of all parties," spokesman Lin Jian said.

In Taiwan, which relies heavily on a long-time security agreement with the United States, President Lai Ching-te said his government would propose record defence spending equivalent to over $35 billion for 2027.

China claims Taiwan is part of its territory and has threatened to use force to annex the self-ruled island.

Unclear benefit

The US-South Korean drills comprise 18,000 South Korean troops and counterparts from US forces, and will focus strongly on drone warfare, GPS disruption, and the role of cyberattacks, Colonel Donald had said.

Downsizing the exercise will "damage alliance coordination, slow the process of South Korea taking on greater responsibility for its own defence, and weaken deterrence against possible conflicts in Asia", Leif-Eric Easley, a professor of international studies at Ewha Womans University in Seoul, told AFP.

Lim Eul-chul, a North Korea expert at Kyungnam University, told AFP Pyongyang was unlikely to be moved by Trump's announcement.

"The North will only view it as meaningful if the joint exercises are cancelled in their entirety rather than scaled back," he said.

Experts say North Korea has expanded its nuclear and missile capabilities since the breakdown of Trump's negotiations with Kim, whom he last met in person in 2019.

Kyiv recently said that up to 50,000 North Korean troops are due to deploy to Russia, although it has provided no evidence or a timeframe for the deployment.

Ukrainian President Volodymyr Zelensky, in making the claim, asked Seoul to supply air defence systems to protect against Russian missiles, a request that has gone unanswered by the South.

US President Trump

Trump says US scaling back military drills with Seoul hours before start