Trump orders Pentagon to cut back military exercises with South Korea

United States President Donald Trump on Sunday instructed the Pentagon to "substantially reduce" joint military exercises with long-term Asian ally South Korea, citing the cost of the drills and Seoul's refusal to take part in actions against Iran.

Hours before exercises were scheduled to begin, Trump said on his Truth Social site he was "not happy" that the US had agreed to participate and highlighted his "very good relationship" with Kim Jong Un, the leader of nuclear-armed and heavily sanctioned North Korea.

"These exercises are not only costly...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," Trump wrote.

The annual Ulchi Freedom Shield joint military exercises are scheduled to run until August 27, with about 18,000 South Korean military personnel participating.

South Korea's Joint Chiefs of Staff told Reuters the drills started on Monday as scheduled, but declined comment on Trump's remarks. The country's presidential office and defence and foreign ministries did not immediately respond on a public holiday in Seoul.

A Pentagon spokesperson referred questions on the matter to the White House, which did not immediately respond to a request for details.

Up-and-down relationship

Trump has has long sought to end or curtail military exercises with South Korea while clashing with Seoul over sharing the costs of stationing 28,500 US troops in South Korea and their role in securing the broader region.

North Korea, still technically at war with the South, routinely denounces the US-South Korean exercises as preparations for an invasion. Pyongyang last week fired a ballistic missile from its eastern coast towards the Sea of Japan, the South Korean and Japanese militaries said, days after a similar North Korean short-range ballistic missile launch.

"This decision may be part of a larger effort to create a diplomatic opportunity with Pyongyang, as Trump has consistently wanted since coming back to office, although the haphazard nature of this move is unlikely to make much of an impression in Pyongyang," Jenny Town, head of the Stimson Centre think tank's 38 North program, said in an email.

Read: North Korea blames US-led alliance for 'new security crisis' in Asia-Pacific

The relationship between Trump and Kim has been a roller coaster for years.

Trump once mocked the North Korean leader as "little rocket man" and threatened Pyongyang with "fire and fury," while Kim boasted that he would "tame the mentally deranged US dotard with fire."

Yet they also took part in three summits, with Trump declaring, "we fell in love" after exchanging letters with Kim. None of these efforts led to changes in North Korea's nuclear weapons or ballistic missile development.

Even as Trump on Sunday spoke warmly of North Korea, he pointed to South Korea's stance on the US-Israeli conflict with Iran.

"While somewhat unrelated (?), I recently asked the President of South Korea if they would like to join us in the Denuclearisation of the Islamic Republic of Iran, and they said, 'No thanks!'" Trump wrote.

Exercises shift to simulations

It's unclear how the drills could be cut back, but in recent years, they have shifted away from live-fire exercises to computer-simulated missile and cyberattacks.

Victor Cha, head of the Korea program at Washington’s Centre for Strategic and International Studies, said Trump may be seeking greater influence over North Korea as Pyongyang has been heavily engaged in support of Russia in Ukraine.

"The other way to look at this is that Trump wants to engage Kim as a way to impede the Russia-NK ties," said Cha.

US military officials have said North Korean troops, who have fought alongside Russia in its invasion of Ukraine, have gained experience from the conflict, while Ukraine said last week that North Korean-made missiles were used in a Russian ballistic missile attack on a steel plant in Zaporizhzhia.

A high-ranking US Northern Command official, Lieutenant General Joseph Jarrard, last week warned that North Korea had successfully tested intercontinental ballistic missiles with "enough boost to deliver a nuclear payload anywhere in North America."

Economic factors

While Trump has repeatedly called for South Korea to shoulder a bigger burden of defence costs, a US official this year called Seoul a "model ally" committed to increasing defense spending in line with US regional strategy.

There are also broader economic tensions.

A former US official who worked in the first Trump administration told Reuters he believed Trump is "frustrated with the intransigence" of the South Korean administration of President Lee Jae Myung in addressing economic issues.

Read More: North Korea's Kim says country will exercise its position as nuclear state, KCNA reports​​

“The Lee government has repeatedly pursued policies antagonistic to American companies and shown little interest in following through on the historic investment deal with the United States," the official said.

The countries signed a trade deal last year to lower Trump's auto tariffs in exchange of Seoul's commitment to invest $350 billion. South Korea has not announced details of its investment plan.

The allies have been at odds over a dispute involving US-listed e-commerce company Coupang, which is being investigated by Seoul over a massive data leak.