President Donald Trump has played down the significance of recent North Korean missile launches, saying in Japan that the tests did not bother him in comments that appeared to undermine John Bolton, his national security adviser.

“North Korea fired off some small weapons, which disturbed some of my people, and others, but not me,” Mr Trump tweeted on the second day of his four-day state visit to Japan, which will include talks about North Korea.

His comment came a day after Mr Bolton told reporters in Tokyo that there was “no doubt” that two sets of recent North Korean missile launches had breached UN Security Council resolutions banning ballistic missile tests.

“I think the prime minister and president are going to talk about making sure the integrity of the UN Security Council resolutions are maintained,” Mr Bolton said just hours before Air Force One landed in Tokyo on Saturday evening.

Mr Trump is expected to discuss North Korea during his meetings with Mr Abe. The US president will play golf with the Japanese prime minister on Sunday morning before accompanying the Japanese leader to watch the final day of a Sumo championship. The two leaders will also have further talks on Monday after Mr Trump has an audience with Emperor Naruhito, who recently ascended the Chrysanthemum Throne after his father became the first emperor to abdicate in 200 years.

North Korea this month launched three ballistic missiles over the course of several days, marking the first such launches since 2017. Some experts interpreted the move as an attempt to put pressure on the US to ease the denuclearisation demands that Mr Trump made during his failed summit with Kim Jong Un in Hanoi in February.

Mr Trump originally said that nobody was “happy” with the tests, but he has since played down concerns, saying he thought Mr Kim was intent on reaching a deal that would remove nuclear weapons from the Korean peninsula.

“I have confidence that Chairman Kim will keep his promise to me,” Mr Trump said in his tweet on Saturday.

Mr Trump added that he smiled when North Korea recently slammed Joe Biden as having a “low IQ” after the former vice-president and now Democratic presidential contender said Mr Trump had been foolish to trust North Korea.

“Also smiled when he called Swampman Joe Bidan [sic] a low IQ individual, & worse. Perhaps that’s sending me a signal?” Mr Trump said.

Negotiations between Washington and Pyongyang have stalled in the wake of Hanoi. At the summit in the Vietnamese capital, Mr Trump refused to accept a limited deal that would have seen North Korea destroy its Yongbyon nuclear facility in exchange for the lifting of some sanctions. Mr Trump insisted that Mr Kim had to abandon his entire programme in order for the US to start lifting any of the economic sanctions that have hurt the North Korean economy.

Talks between Pyongyang and Seoul have also paused since Hanoi. South Korea has tried to resurrect talks by downplaying the missile tests. South Korean president Moon Jae-in has also proposed to meet Mr Kim and has pledged to boost humanitarian aid to North Korea.

“We will do our best to steadily improve inter-Korean relations in a way that will lead to the resumption of North Korea-US talks at an early date,” Kim Yeon-chul, South Korea’s unification minister, said on Friday.

In the weeks since the missile tests, North Korea has shown no sign of wanting to rush back to the negotiating table. North Korea’s foreign ministry on Friday said talks would not resume unless the US took a softer approach on denuclearisation.

“Unless the US puts aside the current method of calculation and comes forward with a new method of calculation . . . dialogue will never be resumed,” a foreign ministry official was quoted as saying by North Korean state media.

Further fuelling tension, Pyongyang this week issued a fresh rebuke over the US seizure of a North Korean cargo ship used to help North Korea export coal in contravention of UN sanctions. The US seized the Wise Honest last year, but the move was not made public until early May as part of a request to a US court to allow the US to take ownership of the vessel.

Han Tae Song, North Korea’s ambassador to the UN in Geneva, told Reuters this week that the ship was “the biggest issue” in improving ties and that Washington had to make a “big decision” on easing sanctions before talks could resume.