Hillary Clinton urges Asia to get tough on North Korea

US secretary of state Hillary Clinton urged Asia today to vigorously apply sanctions against North Korea, saying Pyongyang's belligerent actions marked a clear regional threat.

Clinton, speaking in Hanoi at the Asia-Pacific's biggest security dialogue, also called on Myanmar's neighbours to pressure the country's military rulers for democratic reforms, and said Asia must join the global community in sending a "clear signal" to Iran to rein in its nuclear ambitions.

"One measure of the strength of a community of nations is how it responds to threats to its members, neighbours and region," Clinton told the 27-member Association of South East Asian Nations (ASEAN) regional forum, which includes regional powers China, Japan, and Russia along with the United States, the European Union and Canada.

Clinton on Wednesday unveiled new US sanctions against North Korea, which both Washington and Seoul blame for the March sinking of a South Korean warship which killed 46 sailors and sharpened tensions over Pyongyang's nuclear programme.

The new US sanctions, which target North Korea's ruling elite, build on earlier UN sanctions which imposed broad curbs on dealings with North Korea in the hope of persuading it to abandon its nuclear ambitions.

Clinton said it was essential for Asian nations to enforce these sanctions to encourage North Korea "to take the steps it must" to stop nuclear development and seek real peace with South Korea.

Clinton also urged Asia-Pacific ministers to put more pressure on Myanmar a member of ASEAN which anchors the forum, to enact real democratic reforms and allow elections later this year which will be both free and credible.

The Obama administration has expressed frustration that despite US offers of greater engagement, Myanmar's military rulers have refused to budge on key demands, including freeing an estimated 2,000 political prisoners such as Nobel Peace laureate Aung San Suu Kyi.

It has also said it is concerned by reports that Myanmar, formerly known as Burma, is seeking North Korean help to develop its own nuclear programme, which if true could open an alarming new front in the battle against global nuclear proliferation.

"What's happening in Burma is not only dangerous for the people who endure life under the regime, though they are first and foremost on our minds," Clinton said, adding there was a direct link between open and free societies and political and economic stability.

Clinton's visit to Hanoi is part of the Obama administration's broader effort to boost US engagement with Asia, in part to counter the rising influence of China.

Clinton said she would return to Vietnam in November for another regional summit, and that president Barack Obama would invite ASEAN leaders to a Washington summit in coming months.

Clinton urged regional leaders to resolve standing territorial disputes over the South China Sea, which have pitted China against Vietnam and other countries in the region in squabbles over the vast, potentially oil-rich maritime region.

Clinton said Washington took no sides in the various disputes but did have a strong interest in maintaining open and peaceful sea transit and shipping routes and hoped that all parties would approach the issue in accordance with international law.

"Legitimate claims to maritime space in the South China Sea should be derived solely from legitimate claims to land features," Clinton said, adding that Washington stands ready to facilitate confidence-building measures to help defuse tensions.