The United States announced fresh sanctions on North Korea on Thursday, increasing the economic pressure on the regime of Kim Jong-un as world leaders gathered at the United Nations general assembly in New York.

At a meeting with the leaders of Japan and South Korea on the fringes of the UN gathering, US president Donald Trump announced he had signed an executive order introducing tougher sanctions on Pyongyang.

The new measures will target institutions that “finance and facilitate” trade with the nuclear state, with the order giving the US Treasury new powers to implement the sanctions. “North Korea’s nuclear programme is a grave threat to peace and security in our world, and it is unacceptable that others financially support this criminal, rogue regime,” Mr Trump said, adding that the United States continues to seek a “complete denuclearisation of North Korea”.

In addition, he disclosed that China had agreed to order Chinese banks to stop doing trade with North Korean entities, a move he described as “very bold” and “somewhat unexpected”. The Trump administration has been pushing China to do more to stem the North Korean nuclear threat, particularly in the economic sphere, given that China is North Korea’s primary trading partner and the main supplier of the country’s oil.

Mr Trump said that while the United States had been dealing with the North Korean issue for 25 years, previous administrations had done “nothing,” “which is why we are in the problem we are in today.”

The new order will give treasury secretary Steve Mnuchin the “discretion to target any foreign bank knowingly facilitating specific transactions tied to trade with North Korea”, he said.

Earlier sanctions

The United States has imposed its own sanctions on North Korea in addition to UN sanctions agreed by the UN security council as North Korea’s nuclear activity has intensified.

Last week the security council passed its most stringent measures to date, significantly reducing fuel exports to the country. While the measures fell short of the complete oil embargo proposed by the US, American ambassador to the UN Nikki Haley insisted last week that the sanctions would soon be felt on the North Korean economy.

The European Union also announced its own sanctions on North Korea, though the impact will be minimal considering the low level of trade between the two blocs.

Announcing further details of the sanctions, Mr Mnuchin said that any bank doing business with North Korea would be prohibited from operating in the United States.

“No bank in any country should be used to facilitate Kim Jong-un’s destructive behaviour,” he said. “Foreign financial institutions are now on notice that going forward they can choose to do business with the United States or with North Korea, but not both.”

‘This is deplorable’

Earlier, South Korean leader Moon Jae-in praised American efforts to combat North Korean aggression. “North Korea has continued to make provocations,” he said, during a meeting with Mr Trump, adding: “This is extremely deplorable and has angered both me and our people, but the US has responded firmly and in a very good way.”

In his address to the assembly on Tuesday, Mr Trump warned that the United States may “have no choice but to totally destroy” North Korea.

North Korea’s representative at the UN general assembly described Mr Trump’s threat as “the sound of a dog barking ... If he was thinking he could scare us with the sound of a dog barking, that’s really a dog dream,” foreign minister Ri Yong-ho said.

Mr Ri is due to address the UN on Friday and will meet UN secretary-general António Guterres on Saturday.