Malaysia has charged two women – an Indonesian and a Vietnamese – with murdering the estranged half-brother of North Korea’s leader using a super-toxic nerve agent that killed in minutes.

Siti Aishah, 25, from Jakarta, and Doan Thi Huong, 28, from rural northern Vietnam, could be hanged if they are convicted of the killing of Kim Jong-nam at Kuala Lumpur International airport on 13 February.

Police brought the two women to court handcuffed. As they left, they were made to wear bulletproof vests, reflecting the Malaysian authorities’ fears that others involved in the killing may want the women silenced.

No plea was recorded after the charges were read out against them.

The charges came as a high-level North Korean delegation arrived in Kuala Lumpur. The killing, described by the US and South Korea as a political assassination, has led to a diplomatic meltdown between Malaysia and North Korea, which has repeatedly tried to block the investigation and denied that Kim Jong-nam was murdered.

The visiting delegation includes Ri Tong-il, the former North Korean deputy ambassador to the United Nations. He told reporters on Tuesday that the diplomats were in Malaysia to seek the retrieval of the body and the release of another suspect, a North Korean national.

Ri Tong-il added that the delegation also sought the "development of friendly relationships” between North Korea and Malaysia.

Malaysian police say the two female suspects rubbed VX, the world’s most deadly nerve agent, on Kim’s face in an assault recorded by airport security cameras.

Both of the accused women said they had been duped, believing the assault to be a prank for a reality TV show. The Indonesian suspect, Siti Aisyah, said she had been paid $90 (£72), an Indonesian official has said.

Apandi said the North Korean in custody, named Ri Jong Chol, would not be charged yet. His remand period ends on Friday.

Malaysian police are looking for seven other North Koreans, including a senior diplomat, who they say are linked to the death. Four North Korean suspects left on the day of the killing for Pyongyang, the North Korean capital, police said.

South Korean politicians said on Monday that the country’s national intelligence service had told them in a private briefing that four of the North Koreans identified as suspects were from the ministry of state security, the North’s spy service.

North Korea has not acknowledged the dead man is Kim-Jong-nam but its ambassador, Kang Chol, has repeatedly demanded no autopsy take place and accused Malaysia of acting in a deceiving manner.

Malaysia’s foreign minister, Anifah Aman, has responded by warning Kang that he would be thrown out of the country if he continued to "spew lies” over the investigation.

In a report from North Korea’s state-run KCNA news agency on Friday, the government said Malaysia had broken international law by conducting autopsies on a diplomatic passport holder and withholding the body.

"This proves that the Malaysian side is going to politicise the transfer of the body in utter disregard of international law and morality and thus attain a sinister purpose,” it said.

Kim, who had criticised his half-brother in the past, had been living in the Chinese territory of Macau.

Police say Siti Aishah vomited in the taxi after the attack, possibly due to the effects of VX on her hands. The Vietnamese suspect, Doan Thi Huong, stayed at the cheapest room in a hotel near the airport before the attack and carried a wad of cash.

After the assault, Kim stumbled into a clinic, complaining of pain in his face and dizziness. He died within 15-20 minutes, Malaysia’s health minister has said.

VX nerve agent is a banned chemical substance classified by the UN as a weapon of mass destruction.

Yun Byung-se, South Korea’s foreign minister, told the UN-sponsored Conference on Disarmament on Tuesday: "North Korea is reported to have not just grams but thousands of tonnes of chemical weapons including VX all over the country … The recent assassination is a wakeup call to all of us to North Korea’s chemical weapons capability and its intent to actually use them.”

Yun said that states could invoke the chemical weapons convention and take collective measures against Pyongyang. "It could take the form of suspension of North Korea’s rights and privileges as a UN member,” he said.

Malaysia has insisted that the killing poses no danger to the public and has declared its international airport a "safe zone”. Authorities have said there have been no anomalies in medical cases reported at the airport clinic since the incident.

Police are also searching other locations in Kuala Lumpur that suspects may have visited, including raiding an apartment in an upscale suburb earlier this week to check for any traces of unusual chemicals.

Agencies