UN Secretary General Antonio Guterres said he is "deeply concerned" about North Korea's indication on Wednesday that it could resume nuclear and missile tests.
The statement comes a day after North Korean leader Kim Jong Un said that North Korea was developing a new "strategic weapon" and that the country no longer considered itself bound by a self-imposed moratorium on nuclear and missile tests.
"The Secretary-General very much hopes that the tests will not resume, in line with relevant Security Council resolutions," Guterres' spokesman Stephane Dujarric said in a statement on Wednesday.
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"Non-proliferation remains a fundamental pillar of global nuclear security and must be preserved," he added.
"Diplomatic engagement is the only pathway to sustainable peace."
Trump: Kim is a 'man of his word'
US President Donald Trump said after Kim's remarks that the leader had signed a denuclearization contract and that he believed that Kim was a "man of his word."
"If Chairman Kim has reneged on the commitments he made to President Trump, that is deeply disappointing," US Secretary of State Mike Pompeo said.
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North Korean leader Kim had promised a "Christmas gift" to the West, which many commentators say may take the form of renewed missile testing in the region.
North Korea has yet to officially respond to Guterres' or Washington's reactions.
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ed/se (Reuters, AP)