N Korea releases rare photos of Kim at uranium facility

North Korea has for the first time offered a glimpse into a uranium enrichment facility which produces material for its nuclear weapons.

Photographs showed its leader Kim Jong Un, who had earlier vowed to "exponentially" increase the country's stash of nuclear weapons, inspecting the area.

The state's Korean Central News Agency (KCNA) said in a report on Friday that he had similarly called for the uranium facility to increase its production.

Enriched uranium is essential in the manufacturing of nuclear warheads.

The photograph shows Mr Kim walking past rows of centrifuges and talking to military officials. Their publication comes amid heightened tensions on the Korean peninsula.

"[Mr Kim] went round the control room of the uranium enrichment base to learn about the overall operation of the production lines," KCNA reported, adding that he "felt strong" to see the site.

The South Korean government has said it strongly condemns the North's plans to increase production.

It is unclear when Mr Kim made the visit and if the site is at the North's sprawling Yongbyon nuclear complex, which produces fissile material for Pyongyang's nuclear weapons.

One expert said the disclosure of the facility could be a "message" to the upcoming US presidential election, meant to show the next adminstration that it would be "impossible to denuclearise North Korea".

"It is also a message demanding other countries to acknowledge North Korea as a nuclear state," Hong Min, a senior analyst at the Korea Institute for National Unification, told news agency AFP.

South Korea's Ministry of Unification has condemned the North for publicising the facility, adding that the illegal deployment of nuclear weapons violates several resolutions set by the UN Security Council.

"Any nuclear threat or provocation by North Korea will be met with an overwhelming and strong response from our government and military, based on the solid extended deterrence of the South Korea-US alliance," the unification ministry said.

It is not known how many nuclear weapons North Korea has, but one recent estimate puts the number at 50, with sufficient material to produce another 40.

Additional reporting by Kelly Ng in Singapore