North Korea and Malaysia Tuesday banned each other's citizens from leaving their countries, with Kuala Lumpur saying its nationals were effectively being held "hostage" in a row over the assassination of Kim Jong-Nam.
The extraordinary tit-for-tat moves came as the reclusive North faced growing international condemnation for a volley of missiles it fired into the Sea of Japan, defying stringent global sanctions aimed at halting its weapons programme.
Tuesday's developments marked a dramatic heightening of tensions with Malaysia three weeks after the half-brother of North Korean leader Kim Jong-Un was murdered at Malaysia's main airport with the banned VX nerve agent.
The North decided to "temporarily ban the exit of Malaysian citizens in the DPRK", the official news agency KCNA said, citing the foreign ministry and using the country's official name, the Democratic People's Republic of Korea.
The prohibition would remain in place "until the safety of the diplomats and citizens of the DPRK in Malaysia is fully guaranteed through the fair settlement of the case that occurred in Malaysia".
The Malaysian foreign ministry said 11 of its citizens were currently in North Korea -- three embassy staff, six family members and two who work for the UN's World Food Programme.
The WFP said the pair, as UN staffers, "are international civil servants who do not represent any country". It said it took the safety of its staff seriously and was closely monitoring the situation
Malaysian Prime Minister Najib Razak condemned the ban and said he was ordering a similar ban on the movement of "all North Korean citizens in Malaysia". Analysts said they could number around 1,000.
"This abhorrent act, effectively holding our citizens hostage, is in total disregard of all international law and diplomatic norms," Najib said.
He later chaired an emergency national security council meeting.
"We give assurances we will do everything within our means to bring them home safely," Najib said in a statement afterwards on the 11 Malaysians.
- Weapon of mass destruction -
A top foreign ministry official met the number two at Pyongyang's embassy on Tuesday, a senior government official told AFP on condition of anonymity.
"We have to negotiate with them. We have 11 people in North Korea. The situation is tense," he said.
Senior cabinet minister Wan Junaidi Tuanku Jaafar told AFP Malaysia had "very special" ties with China while Beijing had good relations with Pyongyang. "And this is one of the avenues we can explore to resolve the issue amicably."
Pyongyang and Kuala Lumpur had unusually strong links for years, but ties have rapidly degenerated in the weeks since two women wiped a deadly chemical on Kim Jong-Nam's face.
An autopsy revealed that to be VX nerve agent, a substance so dangerous it is classed as a weapon of mass destruction by the UN.
Seoul has blamed Pyongyang for the assassination, and Kuala Lumpur wants to question several North Koreans, although the only one it arrested was released last week for lack of evidence.
The North has never confirmed the dead man's identity, but has denounced the Malaysian investigation as an attempt to smear it.
North Korean ambassador Kang Chol slammed what he called a "pre-targeted investigation by the Malaysian police" on Monday, just before leaving the country after being expelled.
Pyongyang retaliated by formally ordering out his counterpart -- who had already been recalled for consultations.
According to KCNA, the foreign ministry expressed hopes that the Malaysian government would solve the issue "as early as possible" from a position of "goodwill".
Chang Yong-Seok, senior researcher at Seoul National University's Institute for Peace and Unification Studies, said Pyongyang was using the exit ban as leverage to try to prevent the arrest of key suspects holed up in its embassy.
"I think North Korea is worried that once the two suspects are handed over to Malaysian police, they will serve as clear evidence of the North Korean government's involvement."
The escalating row comes as the United Nations Security Council scheduled an emergency meeting to coordinate the global response to the North's latest missile launches, which KCNA said Tuesday were trial runs at hitting "the bases of the US imperialist aggressor forces in Japan".
Three of the four projectiles fired Monday came down provocatively close to Japan, in what observers said was a test of US President Donald Trump's inchoate North Korea policy.
Under UN resolutions, Pyongyang is barred from any use of ballistic missile technology, but six sets of sanctions since its first nuclear test in 2006 have failed to halt its drive for what it insists are defensive weapons.