North Korean Foreign Minister Ri Son-gwon. Yonhap

North Korea sees little use maintaining a personal relationship between leader Kim Jong Un and U.S. President Donald Trump if Washington sticks to hostile policies, state media reported on Friday - the two-year anniversary of the leaders' first summit.

U.S. policies prove Washington remains a long-term threat to the North Korean state and its people and North Korea will develop more reliable military forces to counter that threat, Foreign Minister Ri Son Gwon said in a statement carried by state news agency KCNA.

Trump and Kim exchanged insults and threats during 2017 as North Korea made large advances in its nuclear and missile programme and the United States responded by leading an international effort to tighten sanctions.

Relations improved significantly around the Singapore summit in June 2018, the first time a sitting American president met with a North Korean leader, but the statement that came out of the meeting was light on specifics.

A second summit in February 2019 in Vietnam failed to reach a deal because of conflicts over U.S. calls for North Korea to completely give up its nuclear weapons, and North Korean demands for swift sanctions relief.

Ri said in retrospect the Trump administration appears to have been focusing on only scoring political points while seeking to isolate and suffocate North Korea, and threatening it with preemptive nuclear strikes and regime change.

"Never again will we provide the U.S. chief executive with another package to be used for achievements without receiving any returns," he said. "Nothing is more hypocritical than an empty promise."

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