South Korea warns North Korea’s nuclear site activity ‘increased threefold’ - suggesting new warhead test

Ms Park orders military to be on alert

A missile launched by North Korea in March (EPA)

North Korea could be preparing to launch another missile amid signs of increased activity around its main test site, South Korean President Park Geuin-hye has warned,

South Korean news agency, Yonhap, reported activity at the North’s Punggye-r nuclear test site – where all other previous tests have taken place - had “increased two-to threefold recently.”

Ms Park has ordered military to be ready to deal with any action, according to reports of a meeting held with her top advisor.

In the meeting, Ms Park said: “We are in a situation in which we cannot predict what provocations North Korea might conduct to break away from isolation and to consolidate the regime.”

“Given the latest developments, North Korea could carry out an underground nuclear warhead test, and we are keeping close tabs on it,” Moon Sang-gyun, a defence ministry spokesman, told reporters in Seol on Monday.

Analysts at 38 North, a website devoted to watching North Korea, saidthey also saw increased movement in satellite imagery around the north portal but that there was little evidence Pyongyang was planning an imminent nuclear test.

“Nevertheless, that possibility cannot be entirely ruled out since the North may be able to conduct a nuclear test on short notice with few indications that it intends to do so,” military analyst Jack Liu wrote on the site.

Concerns that Pyongyang may conduct another nuclear test comes as the regime prepares to hold a meeting for its ruling Worker’s Party in May.

South Korean President Park Geun-hye (Rex Features)

North Korea’s leader, Kim Jong Un, is expected to use the meeting to repeat claims made in March of the ability to make nuclear warheads small enough to fit on long-range ballistic missiles.

State media released images in March appeared to show the leader standing next to the nuclear warheads, but the claims have not been verified.

Experts believe the North may be prompted to carry out another nuclear test following the failure of medium-range ballistic missile, attempting to mark the birthday of founding president Kim II Sung, Kim Jong Un’s late grandfather.

The North is thought to the retaliating to the UN’s sanctions imposed on the country in January after the fourth nuclear test.