In a statement published by the state news agency KCNA on Thursday, North Korea's Foreign Ministry commented on what it called obstacles to the implementation of the June 12 Trump-Kim agreement, blasting US attempts to build up "international pressure."
It said that Pyongyang had stopped nuclear and missile tests, dismantled a nuclear test ground and returned the remains of US soldiers killed in the 1950-53 Korean War, warning, however, that the implementation of the joint North Korea-US statement would be impossible if the US followed an "outdated acting script."
The Ministry accused high-level American officials of "going against the intention of President Trump" by "making baseless allegations against us and making desperate attempts at intensifying the international sanctions and pressure."
Pyongyang also noted that it was still willing to stick to a broad agreement made at the landmark Trump-Kim summit in June.
This follows a statement by the US ambassador to the United Nations Nikki Haley, who warned on Thursday that Washington was "not willing to wait for too long" for North Korea to work towards denuclearization.
Her comments came the day after Trump's national security adviser, John Bolton, said that North Korea had not made the necessary progress toward denuclearization, adding that Washington wouldn't reduce pressure on Pyongyang until it gives up its nuclear weapons.
At the historic talks with US President Donald Trump in Singapore on June 12, North Korea leader Kim Jong-un vowed to rid the Korean peninsula of nuclear weapons and build "new relations" with the US, which would provide unspecified "security guarantees" in exchange. The two sides hailed the talks as "tremendous" and "epoch-making"; they wrapped up months of saber-rattling and name-calling that came after the UN Security Council stepped up sanctions on North Korea over its nuclear and ballistic missile tests.