Britain on Monday urged Malaysia to share evidence from the lethal VX nerve gas attack on Kim Jong-Un’s half-brother with the United Nations, which could take action against North Korea.

British Ambassador Matthew Rycroft said information on the February 13 attack at Kuala Lumpur airport that killed Kim Jong-Nam should be sent to the Hague-based Organization for the Prohibition of Chemical Weapons.

“If they have got evidence, they should send it to the OPCW and to the Security Council,” Rycroft told journalists.

“Once they have done that, then we can take it forward.”

Rycroft said he hoped that any country “in this case Malaysia, with potential evidence of something as serious as this, makes it available as soon as possible.”

Japanese Ambassador Koro Bessho said it was up to Malaysia to decide whether it wanted to pass on the information.

“We are basically waiting for Malaysia to come up with a clear-cut decision,” he added.

Malaysia is a signatory to the Chemical Weapons Convention, which seeks to eliminate the use of the toxic agents.

On Friday, the OPCW said in a statement that “the Malaysian authorities seem to have determined that the nerve agent VX was used in a killing at the airport on 13 February.”

“Any use of chemical weapons is deeply disturbing”, it said, adding that the OPCW was ready to offer expertise and technical assistance to Malaysia.

The Malaysian mission to the United Nations did not immediately return enquiries about its plans.

Malaysia’s health minister said Sunday that Kim Jong-Nam suffered a “very painful death”, with the nerve agent severely affecting his heart and lungs.

“From the time of the onset (of the attack) he died within 15 to 20 minutes,” Health Minister S. Subramaniam told reporters.

South Korea slammed the use of the toxin as a “blatant violation of the Chemical Weapons Convention and other international norms”.

North Korea, which has not signed the CWC, has already been hit with six sets of UN sanctions for carrying out nuclear tests and ballistic missile launches