Washington, Tokyo and Seoul have urged UN member states to repatriate North Koreans working overseas, claiming they continue to evade sanctions abroad to finance Pyongyang's unlawful weapons programme.

North Korea was also engaged in "malicious cyber activities" that supported its military expansion, representatives of the three countries said in a joint statement.

The nuclear-armed country has long made a fortune from the army of citizens it sends abroad to work, mostly in neighbouring China and Russia, but also in Europe, the Middle East and Africa.

Under a UN resolution unanimously approved in 2017, member states had until December 2019 to send back all North Koreans working in their countries.

But on Friday, Washington, Tokyo and Seoul said North Korea's overseas workers were continuing to help fund Pyongyang's increasingly aggressive provocations, following a trilateral meeting in the South Korean capital.

Cyber security concerns

The three states also expressed deep concern over North Korea's "malicious" cyber activities to support its weapons programmes, in comments released in the joint statement.

Crypto currency funds stolen by North Korean hackers have been a key source for financing the sanctions-stricken country's weapons programmes, officials and experts in the US and its allies say.

"Overseas DPRK IT workers continue using forged identities and nationalities to evade UNSC sanctions and earn income abroad that funds the DPRK's unlawful weapon of mass destruction and ballistic missile programs," the envoys said in a joint statement, using North Korea's official name.

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"We are also deeply concerned about how the DPRK supports these programmes by stealing and laundering funds as well as gathering information through malicious cyber activities," the statement said, urging UN member states to comply with UN Security Council resolutions to repatriate North Korean workers on their soil.

Missile loop

In 2019, analysts said Beijing and Moscow - Pyongyang's key allies - were issuing North Korean workers with alternative visas to ensure a continued supply of cheap labour.

Last year, North Korea declared itself an "irreversible" nuclear power last year, effectively ending the possibility of denuclearisation talks.

Leader Kim Jong Un ordered his military to intensify drills last month to prepare for a "real war".

In recent weeks, North Korea has tested what state media has claimed was an underwater, nuclear-capable drone and carried out the launch of an intercontinental ballistic missile.

"We strongly condemn the DPRK's repeated ballistic missile launches as well as its escalatory and destabilizing rhetoric related to the use of nuclear weapons," the envoys said.

"We express deep regret that the DPRK continues to ignore the hardship of its people, choosing instead to pour its scarce resources into its WMD and ballistic missile programs in clear violation of multiple United Nations Security Council resolutions."

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