North Korea's global coal exports sunk to zero in April, UN data showed, as China choked off imports from Pyongyang to ramp up pressure on its nuclear-armed neighbour.  

China -- the North's sole major ally and economic lifeline -- announced in February a suspension of coal imports from the North, choking-off a key source of hard currency for Pyongyang, which has rattled the region with an increasingly aggressive weapons programme. 

Data recently updated on the United Nations Security Council website showed a sharp fall in coal shipped from the North to one unnamed country, plunging from 1.4 million tonnes, worth $126 million, in January to zero in April.

The data, based on member states' voluntary reports, did not explicitly name China.

But it may assuage the administration of US President Donald Trump, which has leant heavily on Beijing to help rein in Pyongyang.

Tension is high on the Korean peninsula as the North has staged two atomic tests and dozens of missile launches since the beginning of last year, showing gradual upgrade in its missile capabilities.

The UN Security Council last Friday unanimously adopted a US-drafted resolution imposing new targeted sanctions on a handful of North Korean officials and entities, a move Pyongyang said was "mean".

China supported that decision but has made it clear that a push for talks -- and not more sanctions -- is its priority, calling for a resumption of six-party negotiations that have been dormant since 2009.

Washington says it is willing to enter into talks with Pyongyang, but only if it halts its missile and nuclear tests.

Under UN resolutions North Korea is barred from using nuclear and ballistic missile technology. The North is already under layers of sanctions for past violations of the resolutions.

China's overall once-vibrant trade with the North, rich with coal and other mining resources, fell in April to a near three-year low after the coal import ban took effect.