Emerging after a four-hour meeting in Beijing they both described as "constructive" and "candid", Mr Kerry and Chinese Foreign Minister Wang Yi nonetheless presented sharply contrasting positions on how to respond to North Korea's latest nuclear bomb test, as well as rising tensions over territorial disputes in the South China Sea.

Describing North Korea's nuclear weapons programme as an "overt threat, a declared threat to the world", Mr Kerry had hoped to sway Beijing into supporting new punitive measures reportedly including bans on Chinese oil exports, North Korean mineral imports, and flights between the two nations.

"All nations, particularly those who seek a global leadership role, or have a global leadership role, have a responsibility to deal with this threat," Mr Kerry said.

But Mr Wang said while China agreed on pushing for a new UN resolution, "our position will not be swayed by specific events or the temporary mood of the moment".

"Sanctions are not an end in themselves," he said. "The new resolution should not provoke new tension in the situation, much less destabilise the Korean peninsula".

China remains a key ally and trade partner of North Korea, despite an increasingly volatile Kim Jong-un regime claiming the successful test of a hydrogen bomb earlier this month. While frequently criticised for not using its leverage more effectively, Beijing's long-held position has been to support a diplomatic resolution, believing tougher measures could back an already dangerously volatile North Korea into a corner.

"There is zero chance that Beijing would agree to the [US] proposal," said Shi Yinhong, an international relations professor at Renmin University. "It would cause China to lose all flexibility in handling North Korea and would turn it to a permanently hostile state sitting on the Chinese border."

An editorial by the official Xinhua news agency said while exacerbating the situation on the Korean peninsula was "deplorable", it boiled down to "Uncle Sam's uncompromising hostility … flaring up the country's sense of insecurity and thus pushing it towards reckless nuclear brinkmanship".

Mr Kerry, who is also due to meet with President Xi Jinping, arrived in Beijing on Tuesday night, the final stop on an eight-day diplomatic mission which also took in stops in Cambodia and Laos. There, he called on ASEAN countries to present a united front in dealing with China's increasing assertiveness over disputed territorial claims in the South China Sea.

In Beijing on Thursday, Mr Kerry called on China to halt its rapid programme of land reclamation and construction of airstrips, which has alarmed the region's smaller neighbours. Mr Wang reasserted China's position that it was doing nothing more than protecting its territorial sovereignty, and had no interest in militarising the islands.

Tensions in the strategic waters, which see $US5 trillion in world trade pass through each year, have flared persistently. Recent developments include China's movement of an oil rig back into an area disputed with Vietnam, and warnings against a Philippines overflight.

On Wednesday, tensions came from a more unlikely source, with Taiwan's outgoing president Ma Ying-jeou announcing he would visit the Taiwan-administered Itu Aba, or Taiping, in the Spratly archipelago on Thursday. The island is also claimed by China, the Philippines and Vietnam.

"Such an action is extremely unhelpful and does not contribute to the peaceful resolution of disputes in the South China Sea," said Sonia Urbom, a spokeswoman from the American Institute in Taiwan, which functions as the de facto US embassy in the absence of formal diplomatic ties.

Mr Ma's office said an invitation was also extended to Democratic Progressive Party leader and president-elect Tsai Ing-wen to send a representative. The DPP, which clinched a landslide election victory earlier this month, said it had no plans to do so.

with agencies