KUALA LUMPUR (REUTERS, THE STAR/ASIA NEWS NETWORK) - Malaysia will cancel visa-free entry for North Koreans entering the country from March 6, Deputy Prime Minister Ahmad Zahid Hamidi said on Thursday (March 2) amid a spat between the two countries following the Kim Jong Nam murder.

North Koreans will be required to obtain a visa before entering Malaysia for national security reasons, Ahmad Zahid, who is also Home Minister, was quoted by Bernama as saying.

"I hope the decision of the Home Ministry (to cancel visa-free entry for North Koreans) will be implemented by the Immigration Department for the sake of national security," he told a press conference after the Home Ministry's Excellent Service Award ceremony.

The move comes two weeks after Kim Jong Nam, the estranged half brother of North Korean leader Kim Jong Un, was killed at the Kuala Lumpur airport with the VX toxic nerve agent.

South Korea and US say he was assassinated by agents of the North Korean regime.

Diplomatic ties between Malaysia and North Korea have soured since the murder. North Korea tried to convince Malaysia not to perform an autopsy on Kim Jong Nam's body, and to release three suspects detained in connection with the killing.

Its envoy Kang Chol has also accused Malaysia of colluding with South Korea.

Ahmad Zahid hit back at the allegations on Thursday.

"We act sternly to ensure the safety of our citizens. Do not use Malaysia as a place to execute the antics that you think you can carry out," he said.

"We don't want to make enemies but they have used Malaysia as a site to interpret their own agenda.

"I advise diplomats from North Korea, whether in Malaysia or other international organisations, do not assume Malaysia to be like any other nation that they have disturbed."

Malaysia has charged a Indonesian woman and a Vietnamese woman with murder, but police also want to question seven others, including a senior official in the North Korean embassy in Kuala Lumpur.

It is due to release a North Korean suspect who has been detained for two weeks for suspected involvement in Jong Nam's murder, due to lack of evidence for an indictment.

A high level North Korean diplomatic delegation had arrived in Kuala Lumpur on Tuesday and has held talks with members of the Malaysian Cabinet to press their demands to release the three suspects detained in connection with the killing.

Malaysia has insisted that laws of the country will be followed and has refused to release the body to the North Korean embassy in Kuala Lumpur, while waiting for the next-of-kin to come forward.

The country is considering expelling Kang, the envoy, or shutting Malaysia's embassy in Pyongyang, a senior government official told Reuters last week, when the Malaysian ambassador was recalled for consultations.

Following a Reuters report this week that the North Korean intelligence agency has been running an arms operations from Kuala Lumpur for years, the Malaysian police have said they will strike two related companies off the country's company registry.

The severe strain on the relationship follows decades of friendly ties between the two countries.

North Korea and Malaysia have maintained cosy ties since the 1970s when former prime minister Mahathir Mohamad embraced the isolated state, in part to rebuff the United States.

Malaysian palm oil and rubber are exported to the communist state. Cars made by Malaysian national carmaker Proton have been sold to North Korea and are used as taxis.