North Korea’s leader Kim Jong-un has said that he will dismantle his country’s main nuclear testing site in May and invited South Korean and US experts, and journalists to view the process.

The dictator’s pledge was made to Moon Jae-in, South Korea’s prime minister, during their historic talks on Friday, according to Mr Moon’s spokesman.

As well as promising to close the Punggye-ri bomb testing site Kim said he would change North Korea’s time zone by half an hour, reverting it to match South Korea’s.

Reports of the pledge came as senior White House figures spoke optimistically about hopes for full North Korean denuclearisation.

Secretary of State Mike Pompeo, who held secret talks with Kim in Easter when he was still head of the CIA, said the US has an "obligation" to pursue a diplomatic solution with North Korea.

In an interview with ABC news, he said the US must "engage in diplomatic discourse to try and find a peaceful solution so that Americans aren't held at risk by Kim Jong Un and his nuclear arsenal".