The top diplomats from the United States and China voiced guarded hope Saturday of preventing tensions from spiralling out of control as they held rare talks on the Indonesian island of Bali.

Neither side expected major breakthroughs between Secretary of State Antony Blinken and Foreign Minister Wang Yi, but the two powers have moderated their tone and stepped up interaction at a time when the West is focused on Russia's invasion of Ukraine.

"In a relationship as complex and consequential as the one between the United States and China, there is a lot to talk about," Blinken said as he opened discussions at a resort hotel in Bali, where the pair attended a Group of 20 gathering the day before.

"We very much look forward to a productive and constructive conversation," Blinken said.

Wang said that President Xi Jinping believed in cooperation as well as "mutual respect" between the world's two largest economic powers and that there needed to be "normal exchanges" between them.

"We do need to work together to ensure that this relationship will continue to move forward along the right track," Wang said in front of US and Chinese flags before a day of talks that will include a working lunch.

Daniel Kritenbrink, the top US diplomat for East Asia, earlier said that Blinken will seek "guardrails" in the US rivalry with China and do "everything possible to ensure that we prevent any miscalculation that could lead inadvertently to conflict".

It is Blinken and Wang's first in-person meeting since October. They are expected to prepare for virtual talks in the coming weeks between Xi and President Joe Biden.

After a long chill during the pandemic between the two countries, since last month their defence, finance and national security chiefs as well as their top military commanders have all spoken.

China's state-run Global Times, known for its criticism of the United States, wrote that the growing diplomacy "underscored the two sides' consensus on avoiding escalating confrontation".

But tensions remain high, especially on Taiwan, with the United States airing concern that China is stepping up pressure on the self-ruling democracy, which it considers part of its territory.

- China 'subdued' on Ukraine -

US views of China have hardened in recent years and Biden has largely maintained the substance of his predecessor Donald Trump's hardline approach of treating Beijing as the pre-eminent global competitor of the United States.

But Blinken in a recent speech made clear that the United States was not seeking a new "Cold War," even as he held firm on criticism -- including accusing Beijing of genocide against the mostly Muslim Uyghur people.

The Biden administration is widely expected soon to ease some of Trump's tariffs on Chinese goods, a move that could ease soaring inflation, which has become a major political liability in the United States.

US officials have also been cautiously upbeat about China's stance on Ukraine, condemning its rhetorical backing of Russia but seeing no sign that Beijing is backing its words with material support.

"What was striking was how measured and, sort of, subdued" China was on Ukraine during Friday's closed-door G20 talks, one official said. 

The US is leading attempts to isolate Russian Foreign Minister Sergei Lavrov, who diplomats said walked out of the meeting following Western criticism.

Wang did not offer "any full-throated endorsement or any sort of signal that China and Russia have this kind of pact," the official said on condition of anonymity.

US officials are keenly aware that any mini-honeymoon with China could be fleeting.

Xi, China's most powerful leader in decades, is expected to shake up the foreign policy team at the Communist Party's National Congress later this year.

But Craig Singleton, who follows China at the hawkish Washington-based Foundation for Defense of Democracies, expected Xi again to appoint technocrats who can work with Washington.

"The reason is simply -- China's economy is facing considerable headwinds and Chinese policymakers appear eager to recognise that China's aggressive rhetoric has backfired," he said.