The ministry remarked that the outcome of the talks was “very concerning” since it has led to a “dangerous phase that might rattle our willingness for denuclearization that had been firm.”

Several weeks after a historic Singapore-hosted meeting between U.S. President Donald Trump and North Korean leader Kim Jong-un, both countries remain at odds.

Kim has accused the Trump Administration of making “gangster-like” demands regarding a denuclearization deal with the Asian nation, following a third visit to Pyongyang by U.S. Secretary of State Mike Pompeo. “The issues the U.S. side insisted on during the talks were the same cancerous ones that the past U.S. administrations had insisted on,” the North Korea's foreign ministry said.

Pompeo said the discussion includes “achieving what Chairman Kim and President Trump both agreed to, which is the complete denuclearization of North Korea. No one walked away from that, they’re still equally committed, Chairman Kim is still committed.”

The ministry remarked that the outcome of the talks was “very concerning” since it has led to a “dangerous phase that might rattle our willingness for denuclearization that had been firm.”

The ministry added: “We had expected that the U.S. side would offer constructive measures that would help build trust based on the spirit of the leaders' summit... we were also thinking about providing reciprocal measures.

“However, the attitude and stance the United States showed in the first high-level meeting (between the countries) was no doubt regrettable. Our expectations and hopes were so naive it could be called foolish.”

U.S. officials claim that the two countries have established working groups to address the details of and implement an agreement. While the North, in a statement by Korean Central News Agency, described the visit as “regrettable,” explaining that the United States had suddenly introduced “conditions and excuses” to circumvent a request to formally end the Korean War.

North Korea also accused the United States of trivializing the significance of suspending military exercises with South Korea.

UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator Mark Lowcock is due to meet North Korean officials and visit UN projects across the country on Monday.