U.N. Secretary General Antonio Guterres welcomed on Monday the planned closing of North Korea's nuclear test site as a positive move ahead of a summit between the top leaders of the United States and North Korea scheduled to take place next month.

The U.N. chief believes that "the irreversible closure of the site will be an important confidence-building measure that will contribute to further efforts towards sustainable peace and verifiable denuclearization of the Korean Peninsula," he said in a statement.

North Korea is set to hold a ceremony for dismantling the nuclear test site in Punggye-ri between May 23 and 25, depending on weather conditions, ahead of the June 12 meeting in Singapore between U.S President Donald Trump and North Korean leader Kim Jong Un.

Guterres in the statement also said that he "looks forward to this positive momentum being consolidated at the summit between the leaders of the United States and the DPRK next month."

North Korea's official name is the Democratic People's Republic of Korea.