Australia will urge China to clamp down on the flow of technology and equipment crossing its borders into North Korea, which could be used by the rogue nation in its nuclear weapons program.
This week Foreign Affairs Minister Bob Carr will try to persuade his Chinese counterpart, State Councillor Yang Jiechi, to tighten the enforcement of sanctions backed by the United Nations aimed at forcing the hermit state to abandon its goal of becoming a fully fledged nuclear power.
Amid growing fears that the nation's increasingly aggressive stance towards its southern neighbour could spiral out of control, Senator Carr will raise the issue during a visit of an Australian delegation to China this week led by Prime Minister Julia Gillard.
The development came as tensions increased on the Korean Peninsula with South Korean President Park Geun-hye vowing ''a strong response'' to any provocation from the north.
Her remarks followed the declaration by the young North Korean leader Kim Jong-un that his country was entering ''a state of war'' with its wealthy, democratic neighbour South Korea. North Korea has also issued multiple military threats against the US. And on Sunday President Kim declared the nation's nuclear weapons a ''treasure'' that it would not abandon.
As North Korea's only real ally, China is considered to be the only country with any influence over the intractable and reclusive regime. Senator Carr's spokesman said on Monday that the UN sanctions would be more effective if there was tighter implementation on ships and planes travelling to North Korea, including from China.
''That's something we'll be talking about when we're in China,'' he said. It is not suggested China is breaching the sanctions. China voted for them in the Security Council but China is the principal conduit for supplies to North Korea.
''We're going to emphasise the importance of taking action on North Korea but we appreciate you have to approach that in a manner that recognises their relationship - rather than just bursting in and telling them our view of the world.''
Senator Carr has also said recently that Australia is considering its own sanctions, on top of the UN measures, that would target banking and finance to hit the North Korean elite's hip pocket.
New sanctions imposed by the UN Security Council in response to North Korea's nuclear test in February included tougher financial restrictions and bans on luxury items such as yachts, luxury cars and some types of jewellery and perfumes. But such items are reported still to be flowing into the country, as are goods that could be used in the regime's weapons industries.
The US sent F-22 stealth fighters to South Korea on Sunday as part of military exercises.
Experts are divided about how seriously North Korea's latest outbursts should be taken. Andrei Lankov, a Korea expert at Kookmin University in the South Korean capital, Seoul, said the latest behaviour followed a familiar pattern.
''They do it once every two or three years. It's how things have been done in Pyongyang for decades. They have not the slightest intention to carry it out because they are not suicidal.''
But Leonid Petrov, a Korea scholar at the University of Sydney, said: ''This time it's much more serious.''
North Korea had made considerable strides in developing nuclear weapons and the rockets to deliver them, he said. ''It means destabilisation in the region is going to continue.''
Ms Gillard will lead the five-day visit by the high-powered delegation to China starting on Friday.
She will meet the new President, Xi Jinping, and Premier Li Keqiang and discuss issues ranging from trade to security and climate change.