Malaysia will cancel visa-free entry for North Koreans entering the country starting next week as diplomatic ties between the two countries fray further following the murder of Kim Jong-nam at the Kuala Lumpur airport.

North Koreans will be required to obtain a visa as of March 6 before entering Malaysia for national security reasons, state news agency Bernama reported on Thursday, citing the deputy prime minister Ahmad Zahid Hamidi.

Malaysia is one of the few countries that North Koreans could visit without a visa. A reciprocal arrangement made Malaysians the only foreigners given visa-free entry to the secretive, nuclear-armed state.

Malaysia police: VX nerve agent killed Kim Jong-nam

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, allegedly with a toxic nerve agent.

Diplomatic ties between Malaysia and North Korea have soured since the murder, which South Korea and the US say was an assassination organised by North Korean agents.

North Korea has denied the accusations and called the allegation that the chemical weapon VX was used in killing "absurd".

North Korea tried to convince Malaysia not to perform an autopsy on Kim's body, and to release a North Korean suspect detained in connection with the murder.

A high-level North Korean diplomatic delegation arrived in Kuala Lumpur on Tuesday and has held talks with members of the Malaysian cabinet to press those demands.

Malaysia has charged an Indonesian woman and a Vietnamese woman with murder. Police are also seeking to question seven others, including a senior official in the North Korean embassy in Kuala Lumpur.

READ MORE: Who produced the VX poison that killed Kim Jong-nam?

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 next of kin to come forward.

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

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

Women charged with killing North Korean leader's brother

Source: Reuters news agency