Chinese President Xi Jinping said Sunday that Asia faced "new challenges" to its stability and warned no one should be allowed to throw the region into chaos as tensions mounted over North Korea.

Xi, delivering a speech at an annual international forum on the southern Chinese island of Hainan, did not mention the crisis on the Korean Peninsula or China's territorial disputes with Japan and Southeast Asian nations.

But he said there should be no tolerance for those who foster "chaos for selfish gains" and reiterated that China would "firmly" uphold its "sovereignty" and "territorial integrity".

Tensions have soared in recent weeks with North Korea threatening nuclear war after the United Nations imposed fresh sanctions over its latest atomic test and the US and South Korea launched joint war games.

"We need to make concerted efforts to resolve major difficulties to ensure stability in Asia," Xi said.

"Stability in Asia now faces new challenges as hot spot issues keep emerging and both traditional and non-traditional security threats exist," he added.

China has traditionally been North Korea's closest political ally since they fought together in the 1950-1953 Korean War and is Pyongyang's biggest trading partner.

Speaking more broadly, Xi called on the international community to push for a "vision of comprehensive security, common security and cooperative security".

Xi said that was necessary so the world could become a stage for the pursuit of "common development", as opposed to one "where gladiators fight each other".

"And no one should be allowed to throw a region, even the whole world, into chaos for selfish gains," he added.

Australian Prime Minister Julia Gillard echoed Xi, saying "all countries in the region share a deep interest in strategic stability".

But Gillard, who has been critical of Pyongyang, singled out North Korea, saying the Korean Peninsula situation illustrated the potential consequences of conflict.

"There, any aggression is a threat to the interests of every country in the region," she said in her speech, hailing "the growing cooperation of all regional governments to prevent conflict on the Korean Peninsula and to counter North Korean aggression".

Alexander Downer, a former Australian foreign minister who listened to the speeches, said it was not surprising that Xi did not mention North Korea by name as it was not something a Chinese president would do.

"I thought he was alluding to it," Downer added. "And I think in a very clever way, which was very reassuring to people."

It was Xi's first attendance at the Boao Forum for Asia since becoming China's president last month. He took over as head of the ruling Communist Party in November and now holds the country's two most powerful positions.

In an apparent reference to territorial disputes, Xi said while China would "properly handle differences and frictions with relevant countries", it would continue to press its claims.

"On the basis of firmly upholding its sovereignty, security and territorial integrity, China will maintain good relations with its neighbours and overall peace and stability in our region," he said.

Beijing and Tokyo are at odds over small, uninhabited islands in the East China Sea administered by Japan but also claimed by China.

China is also engaged in disputes with some Southeast Asian countries including the Philippines and Vietnam over islands and reefs in the South China Sea.

Touted as an Asian version of the World Economic Forum, the three-day Boao gathering has brought together leaders in government, business and academia in Asia and other continents every year since 2001 to discuss pressing issues in the region and the rest of the world.

Among political and financial leaders at this year's event are Myanmar President Thein Sein, International Monetary Fund managing director Christine Lagarde, Mexican President Enrique Pena Nieto and Yasuo Fukuda, a former Japanese prime minister.