North Korea has warned that there has been no progress in relations with the US, and that hostilities that could lead to an exchange of fire have continued.

In a statement under the name of the chairman of the Korea-Asia Pacific Peace Committee, Kim Yong-chol, North Korean state news agency KCNA said on Sunday that it would be a mistake for the US to ignore a year-end deadline on Donald Trump’s and Kim Jong-un’s “close personal relations”.

Kim has set an end-of-year deadline for denuclearisation talks with Washington.

Kim Yong-chol was the envoy for nuclear talks with the US before the second summit between Trump and Kim, in Vietnam in February, ended in failure. In Sunday’s statement he said the US has been pressuring North Korea in a “more crafty and vicious way” instead of heeding North Korea’s call for Washington to adopt a new approach, adding that the US has been persistently pushing other countries to impose UN sanctions on North Korea.

Kim Yong-chol was quoted as saying that the persisting hostility means “there can be the exchange of fire at any moment”, and that he hoped that US-North Korean relations do not show that “there are permanent foes but no permanent friends”.

The statement comes just days after North Korea asked South Korea to discuss removal of its facilities from the North’s resort of Mount Kumgang, a key symbol of cooperation that Pyongyang recently criticised as “shabby” and “capitalist”.

North Korea on Friday sent notices to the South’s unification ministry, which handles issues between the two sides, and Hyundai Group, whose affiliate Hyundai Asan Corp built the resort facilities, asking for their demolition and seeking discussion through the exchange of documents, the ministry said.