WASHINGTON • White House National Security Adviser H.R. McMaster has warned that shipping companies caught smuggling goods into North Korea could be making their "last delivery" anywhere.

Mr McMaster said United Nations sanctions have not halted deliveries of essential goods like refined fuel products that North Korea wants. The smuggling is done by ship-to-ship transfers, he said, suggesting that foreign vessels are moving the goods on the high seas to North Korean ships that take them ashore.

"We've seen quite a bit of that in ship-to-ship transfers of refined fuel products, for example," Mr McMaster said on Tuesday at an event in Washington hosted by the British think-tank Policy Exchange.

"Any company whose ships engage in that ought to face the most severe economic consequences and sanctions."

"A company whose ships would engage in that activity ought to be on notice that that might be the last delivery of anything they do for a long time, anywhere."

Washington remains frustrated that international sanctions on Pyongyang have not resulted in the North halting its nuclear and long-range ballistic missile tests. On Nov 29, North Korea test-fired a nuclear-capable missile that showed the potential to strike anywhere on the continental US.

The US in particular has pressured China to shut down a pipeline delivering crude oil to North Korea, which it hopes would place enough economic pressure on Pyongyang to force it to halt its nuclear activities.

Mr McMaster called on the international community to go beyond UN sanctions to pressure North Korea, saying it "might be our last best chance to avoid military conflict".

AGENCE FRANCE-PRESSE