North Korea has accused the US of being "hell-bent on hostile acts", despite a recent agreement between the two countries to resume nuclear talks.
Pyongyang's delegation to the United Nations said on Wednesday that the US was "obsessed with sanctions".
This comes days after the countries' two leaders held a historic meeting in the heavily fortified demilitarised zone which divides the two Koreas.
Donald Trump became the first sitting US president to set foot in the North.
And after talks that lasted for almost an hour, the pair agreed to set up teams to resume stalled negotiations on denuclearisation.
But the latest North Korean statement marks a shift in tone and a return to the angry exchanges that have marred relations between the countries in recent times.
North Korea also accused Washington of attempting to "undermine the peaceful atmosphere" on the Korean peninsula.
What did North Korea say?
The North Korean delegation said it was responding to a US allegation that it had breached a cap on refined petroleum imports that was set in 2017.
It also said it was responding to a joint letter sent by the US, France, Germany and the UK to all UN member states that called for further sanctions on North Korea.
The letter reportedly asked all members to send expatriate North Korean workers home.
"What can't be overlooked is the fact that this joint letter game was carried out... on the very same day when President Trump proposed [a] summit meeting," the statement read.
"[It] speaks to the reality that the United States is practically more and more hell-bent [on] hostile acts against the DPRK [North Korea]."
"All UN member states will have to keep vigilance against deliberate attempts by the United States to undermine the peaceful atmosphere that has been created on the Korean Peninsula," it said.
Pyongyang added that it was "quite ridiculous" for the US to view sanctions as a "panacea for all problems".
The US is yet to respond to the statement.