North Korea has said the US is "hell-bent on hostile acts" and "obsessed with sanctions" just three days after the two countries agreed to resume to nuclear negotiations.

US President Donald Trump and North Korean leader Kim Jong Un agreed that the two countries would resume talks after a historic meeting that saw Trump become the first US president to enter North Korean territory.

But a statement from North Korea's United Nations delegation suggests a more heated relationship, as it accused the US of "considering sanctions as a panacea for all problems."

North Korea was responding to a letter from the US, France, the UK, and Germany that urged UN member states to impose sanctions against North Korea.

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North Korea has accused the US of being "hell-bent on hostile acts" and "obsessed with sanctions" just three days after US President Donald Trump's historic meeting with North Korean leader Kim Jong Un.

North Korea's delegation to the United Nations on Wednesday said the US was "practically more and more hell-bent on the hostile acts" and is "obsessed with sanctions," Reuters reported.

Trump met with Kim on Sunday and briefly entered North Korean territory, making him the first sitting US president to do so.

Read more: Video shows a 'surreal' and tense encounter between US and North Korean security at the Trump-Kim meeting

The two leaders agreed to resume negotiations that had collapsed in February. Trump has said those talks collapsed after North Korea demanded that sanctions be lifted even before it fully dismantled its nuclear program, though North Korea disputed that account.

Trump and Kim at the DMZ on Sunday. REUTERS/Kevin Lamarque

Trump hailed Sunday's meeting as "wonderful," but North Korea's new statement indicates a return to anger between the two countries.

North Korea said in the statement that the US had made "deliberate attempts" to "undermine the peaceful atmosphere that has been created on the Korean Peninsula in no easy way."

Pyongyang said it was responding to an accusation by the US that it had breached a cap on imports of refined petroleum and to a letter sent by UN Security Council members to other UN states urging them to impose sanctions on North Korea.

Trump had proposed his latest meeting with Kim in a tweet Saturday, the day before the two leaders met, and North Korea said at the time that this was the only proposal it had received.

Read more: Trump administration could drop demand for North Korea's total denuclearization and settle for a 'freeze' instead, New York Times reports

North Korea took issue with the timeline in its statement Wednesday.

"What can't be overlooked is the fact that this joint letter game was carried out by the permanent mission of the United States to the UN under instruction of the State Department, on the very same day when President Trump proposed for the summit meeting," it said.

Trump and Kim during the second US-North Korea summit in Hanoi, Vietnam, on February 2. SAUL LOEB/AFP/Getty Images

According to Reuters, the letter is dated June 27 — last Thursday — and urges UN member states to comply with demands from the UN's sanctions committee to send North Koreans working in other countries back to the country.

The North Korean delegation said Wednesday: "It is quite ridiculous for the United States to continue to behave obsessed with sanctions and pressure campaign against [North Korea], considering sanctions as a panacea for all problems."