Recent satellite imagery shows North Korea has started dismantling facilities at its nuclear test site, according to US researchers.

An analysis on Monday by the 38 North website said commercial imagery taken last week showed several operational support buildings had been razed, and rails for mining carts apparently removed.

North Korea said it will dismantle its Punggye-ri test site between May 23 and 25, in the presence of local and international media.

The site was used for each of its six underground nuclear test explosions.

South Korea’s president on Monday welcomed the announcement as the beginning of North Korea’s nuclear disarmament.

It comes ahead of a historic US-North Korea summit between Kim Jong-Un and Donald Trump in Singapore next month.

North Korea’s Foreign Ministry said on Saturday that all the tunnels at the country’s north-eastern testing ground will be destroyed by explosion, and that observation and research facilities and ground-based guard units will also be removed.

The announcement was immediately welcomed by US President Donald Trump.

“North Korea has announced that they will dismantle Nuclear Test Site this month, ahead of the big Summit Meeting on June 12th,” he tweeted.

North Korea has announced that they will dismantle Nuclear Test Site this month, ahead of the big Summit Meeting on June 12th. Thank you, a very smart and gracious gesture!

— Donald J. Trump (@realDonaldTrump) May 12, 2018

“Thank you, a very smart and gracious gesture!”

The analysis said no tunnel entrances at the test site appeared to have been permanently closed yet.

However, top North Korea defector … has said the North would never completely give up its nuclear weapons.

Thae Yong-ho, who fled his post as the North’s deputy ambassador to Britain in August 2016, said the current whirlwind of negotiations will not end with “a sincere and complete disarmament”, but with “a reduced North Korean nuclear threat”.

“In the end, North Korea will remain ‘a nuclear power packaged as a non-nuclear state’,” Thae told the South’s Newsis news agency.

– with AAP