Palo Alto, California: Secretary of State Rex Tillerson said on Wednesday that North Korea’s government is responsible for the suffering of North Korean people from international economic sanctions imposed over its nuclear weapons. He voiced scepticism that humanitarian aid to alleviate that suffering would reach the people who need it.

Tillerson said, “It’s an unacceptable outcome that Kim [Jong Un] is making that choice, and we’re not going to take any responsibility for the fact that he’s choosing to make his own people suffer.”

Tillerson spoke to reporters aboard his plane back to Washington, a day after meeting with US allies to discuss intensifying sanctions pressure on North Korea. Kim’s authoritarian government is often criticised for spending scarce resources on nuclear and missile development despite chronic malnutrition among its people.

The US stance could put it at odds with close partner South Korea, whose government is re-engaging the rival North after years of escalating tensions and is thought to be considering provision of humanitarian aid through the United Nations, which has a longstanding programme to help feed needy women and children.

Speaking at Stanford University earlier on Wednesday, Tillerson said international sanctions — intended to deprive North Korea of revenue for its weapons and not hurt the wider population — were starting to bite.

He cited Japanese intelligence that 100 North Korean fishing boats had drifted into Japanese waters and two-thirds of the people aboard had died. What the Japanese learned is the North Korean fishermen “are being sent out in the wintertime to fish because there’s food shortages, and they’re being sent out to fish with a lack of fuel to get back,” he said.

Asked about the impact of the sanctions on the broader North Korean population, Tillerson told reporters: “It doesn’t matter which country, when you impose sanctions you are limiting resources available to them and then it’s up to that government to decide how they want to allocate the available resources. So it’s an unavoidable outcome if they make that choice.”

Asked whether humanitarian aid by South Korea would weaken the impact of sanctions, Tillerson implied that the North Korean government might divert the assistance, although according to the UN, there is monitoring of what is provided.

“Our experience with ensuring that aid actually goes to the people who need it is not particularly good,” Tillerson said. “So countries will have to make their own choice, but we would be very sceptical that that aid that goes into the country will necessarily relieve the suffering of the people.”

The Trump administration has galvanised international support for sanctions on North Korea, including by its longtime benefactor China, as the North comes closer to its goal of perfecting a nuclear-tipped missile that can reach the US mainland. That has stoked fears of war.

Tillerson voiced confidence on Wednesday that North Korea would eventually negotiate with the US as the economic pressure grows.