Following the murder of Kim Jong-nam at the Kuala Lumpur airport, Malaysia has decided to cancel visa-free entry for North Koreans into the country after diplomatic ties between the two nations continue to slip.

As of March 6, 2017, North Koreans will be required to obtain a visa before being allowed into the country for national security purposes, Bernama (a state news agency) reported on Thursday, quoting Ahmad Zahid Hamidi, the deputy prime minister.

Malaysia and North Korea had a good relationship since the 1970s when the fourth prime minister of Malaysia Mahathir Mohamad welcomed North Korea with open arms. Trade in resources such as steel and palm oil continued to increase between the two nations leading the North Koreans to establish their embassy in Kuala Lumpur in 2003. Malaysia was one of the few countries that had allowed a visa-free access for North Koreans into the country. As a way of returning the favor the buttoned up and nuclear-armed state only allowed visa-free entry for Malaysians into their country.

The decision comes two weeks after North Korean leader Kim Jong-un’s half-brother, Kim Jong-nam, was allegedly murdered by a toxic nerve agent at the Kuala Lumpur airport. Ever since the diplomatic ties between the two nations took a nose dive in which the US and South Korea suppose was organized by North Korean agents. North Korea has repudiated the accusations and dismissed the allegations that a chemical weapon VX was used to kill Kim Jong-nam.

A high-level delegation of North Korean diplomats arrived in Kuala Lumpur on Tuesday and held a meeting with the Malaysian cabinet members. They were to discourage the performance of an autopsy on Kim’s body and to convince them to release a suspect detained in connection with the murder who was from North Korea, Ri Jong Chol.

Ri Jong Chol, who has lived in Malaysia for the last three years, was arrested four days after Kim’s murder. Police did not provide details on why they arrested him. The Malaysian Attorney General Mohamed Apandi Ali later said that Ri Jong Chol was “a free man” because there was “insufficient evidence to charge him.” Ri Jong Chol will be deported on Friday because he does not have valid travel documents according to the Malaysian authorities.

Siti Aisyah, an Indonesian woman, and Doan Thi Huong, a Vietnamese lady, have been accused by the Malaysian authorities of smearing the nerve agent VX on Kim Jong-nam’s face while he was preparing fly out of the country in Kuala Lumpur airport in the country’s capital. A senior North Korean official in the Kuala Lumpur embassy is on the radar of the Malaysian police as they indicated they want to question him.

The body of Kim Jong-nam has not yet been released to North Korean Kuala Lumpur embassy because they are waiting for the next of kin to present themselves as dictated by the Malaysian law which the country has insisted on following. This stand that was taken by Malaysia has caused tension on the bond between the two nations.