Nuclear talks in Sweden between North Korean and American officials have broken off, the top negotiator for North Korea announced late on Saturday, dashing hopes for an end to months of deadlock.

The talks, held at a remote conference centre outside Stockholm, were the first formal meeting since last June, when U.S. President Donald Trump and North Korean leader Kim Jong Un agreed to restart negotiating following a failed summit in Vietnam in February.

North Korea’s chief nuclear negotiator, Kim Myong Gil, blamed the US for their inflexibility, saying the negotiators from Washington would not “give up their old viewpoint and attitude.”

“The negotiations have not fulfilled our expectation and finally broke off,” Kim told reporters.

The U.S. State Department said that Kim’s comments did not reflect “the content or spirit” of the talks, which lasted almost 9 hours.

“The U.S. brought creative ideas and had good discussions with its DPRK [North Korea] counterparts,” spokeswoman Morgan Ortagus said in a statement.

“The United States and the DPRK will not overcome a legacy of 70 years of war and hostility on the Korean peninsula through the course of a single Saturday,” she added.

“These are weighty issues, and they require a strong commitment by both countries. The United States has that commitment.”

North Korea’s Kim. on the other hand, criticised the U.S. position.

“The U.S. raised expectations by offering suggestions like a flexible approach, new method and creative solutions, but they have disappointed us greatly and dampened our enthusiasm for negotiation by bringing nothing to the negotiation table,” he said.

Washington has accepted Sweden’s invitation to resume the talks with Pyongyang in two weeks. North Korea has not clearly said that it would accept.

Due to its nuclear programme, most of North Korean trade is banned under sanctions.

The U.S. has tried to convince North Korea to return to the negotiating table since June, which appeared to be successful earlier this week when the country suddenly agreed to the talks in Sweden.

On Saturday, the North Korean negotiator said the denuclearisation of the Korean peninsula was still possible but would only happen “when all the obstacles that threaten our safety and check our development are removed completely without a shadow of doubt,” he said, apparently referencing to North Korea’s desire for the US to ease economic pressure.

Only a day after announcing the new talks, North Korea said it had test-fired a new ballistic missile designed for submarine launch, underscoring the need for Washington to move quickly to negotiate limits on Pyongyang’s growing arsenal.

Speaking in Athens on a tour of southern Europe while the talks were still underway, U.S. Secretary of State Mike Pompeo had said he was hopeful of progress.

“We are mindful this will be the first time that we’ve had a chance to have a discussion in quite some time and that there remains to be a lot of work that will have to be done by the two teams,” he told a news conference.

China’s President Xi Jinping and the North’s leader exchanged messages on Sunday to reaffirm the neighbours’ relationship on the 70th anniversary of the establishment of diplomatic ties. China is the North’s only major ally.

Xi, who has met Kim five times in the past year, said they had “reached a series of important consensuses, leading China-North Korea relations into a new historical era”, the official Xinhua news agency said.

“In accordance with the wishes of both countries’ peoples,” Kim replied, the two leaders would “resolutely safeguard the peace and stability of the Korean peninsula and the world.”

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