"We believe there is more other countries can do to put pressure on this nation to change its behaviour, including nations that have financial relationships with North Korea and that, of course, includes China," Ms Bishop said during a two-day visit to Thailand.

Australia toughened its sanctions against North Korea in June amid rising tensions on the Korean peninsular and now has bans on more than 100 individuals, companies or groups associated with North Korea.

Ms Bishop said Australia is open to any initiatives to pressure North Korea, after the United States said it is seeking talks on how Pyongyang could be suspended from the annual 27-member ASEAN Regional Forum in Manila.

North Korea is sending its top diplomat to the forum.

Ms Bishop said the pace and scale of North Korea's testing of ballistic weapons is not only a threat to the region but also to the world, and Australia is "deeply concerned."

"North Korea is in flagrant breach of international laws and Australia wants to work with like-minded countries to change its behaviour," she said.

A draft copy of a chairman's statement to be released after the summit expresses "grave concern" over North Korea's missile tests, according to Agence France Presse.

In Washington, Susan Thornton, a top official in the State Department, said US Secretary of State Rex Tillerson will also be lobbying other countries attending the Manila summit to further isolate North Korea.

"What we've been doing is going around talking to partners about what more they could do to contribute to that increasing pressure on the regime and the increasing sort of diplomatic isolation of the regime," she said.

Earlier Mr Tillerson said the US is not seeking to topple the regime of Kim Jong-un but reiterated Washington's push for Pyongyang to give up its missile and nuclear program through peaceful pressure.

China's Foreign Minister Wang Yi said Beijing "attached great importance" to Mr Tillerson's remarks.

China has agreed to impose some sanctions on North Korea, its long-time ally, but Beijing is also pushing for a resumption of talks between the US and Pyongyang and a de-escalation of tensions over the nuclear program.

Ahead of the summit, Philippine President Rodrigo Duterte issued a blistering attack on Kim Jong-un, describing him as a "crazy man" who is "playing with his toys."

North Korea conducted its latest test of an intercontinental ballistic missile last Saturday in a stepped-up program which it says is needed as a strong deterrent to prevent a hostile United States from attacking it.

Foreign ministers of the 10-member Association of South-East Asian Nations, meeting in Manila ahead of the wider forum, are expected to issue a joint statement on terrorism as Philippine troops continue to battle Islamic State-allied militants who besieged the country's southern town of Malawi.

The battle has prompted fears the militants are gaining a foothold in the region.

The Manila meeting will also discuss China's build up of islands in the South China Sea but a draft communiqu?? seen by reporters indicates the ministers will omit references to China's most controversial activities in the flash point waters, highlighting Beijing's growing clout in the region.

With agencies