US president Donald Trump has put fresh strain on Washington’s security ties with Seoul, saying South Korean president Lee Jae Myung declined a request to assist the US in its military operation against Iran. Trump also questioned the cost of America’s defence commitments to South Korea.Speaking to reporters at the White House on Monday, Trump said he had recently spoken with Lee and asked whether South Korea would “give us a little hand” with Iran, while stressing that Washington did not need assistance.“I called him. I said, ‘Would you like to give us a little hand? We don’t need help with Iran, but if you’d like, give us a hand with Iran.’ He said, ‘No thanks,’” Trump said.Trump then pointed to the US military presence in South Korea and its role in deterring North Korea. “I said, ‘Wait a minute. We have 39,000 soldiers over there, guarding you from Kim Jong Un, your next-door neighbor, and you’re not going to help us on a very easy military operation in Iran. That’s strange,’” he said.Trump said Lee reiterated that Seoul did not want to become involved in the Iran conflict. He questioned the rationale behind continued US defence commitments to South Korea.“I said, ‘Well, why are we involved in helping you?’” Trump said.The US president said he nevertheless wanted to support South Korea, while arguing that the financial burden of protecting allies had become excessive.“When you ask somebody, ‘Would you like to give us a hand?’ and they say, ‘No, thanks,’ and then we’re guarding them from a country and paying ourselves billions–it’s costing us billions and billions of dollars to protect not only them, but other countries,” Trump said.He also referred to NATO, saying the US spends “hundreds of billions” of dollars on the alliance.Meanwhile, Lee Jae Myung called for stronger independent defence capabilities, while defending the country’s annual civil-defence exercises held alongside joint US-South Korea military drills as defensive and not intended to threaten North Korea.The country had on Monday also expressed hope for a resumption of US-North Korea diplomacy to ease tensions on the Korean Peninsula, hours after Trump announced that he had ordered the annual US-South Korea military exercises to be scaled back.Trump’s remarks came after he instructed secretary of war Pete Hegseth to “substantially reduce” joint military exercises with South Korea.Meanwhile, in a post on Truth Social, Trump said he was “not happy” that the US had previously agreed to participate in the exercises.“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 said.Trump described the drills as costly and said they send a signal that is “totally inappropriate and hostile” to North Korea, which he said had been “unthreatening and respectful” during his presidency.Trump said it was too late to cancel the exercises altogether but ordered a reduction in their scale.“Therefore, and based on the fact that it is too late to cancel, I have instructed Secretary of War, Pete Hegseth, to substantially reduce the Joint Military Exercises!” he said.Meanwhile, South Korea had said on Monday that it was closely consulting with Washington on ways to make practical and military contributions to international discussions on a ceasefire in Iran and efforts to restore freedom of navigation in the Strait of Hormuz, South Korean news agency Yonhap reported.