US Secretary of State Antony Blinken said Saturday that while his rare conversations with his Chinese colleague in Indonesia were "constructive", he expressed concern about certain issues, such as Taiwan.

"Despite the complexities of our relationship, I can say with some confidence that our delegations found today's discussions useful, candid, and constructive," Blinken said after an unusually long five hours of talks with Foreign Minister Wang Yi.

However, Blinken stated that he also expressed concerns about Taiwan, Hong Kong, human rights, and Ukraine.

"I conveyed deep concerns of the United States regarding Beijing's increasingly provocate rhetoric and activity towards Taiwan and the vital importance of maintaining peace and stability across the Taiwan Strait," Blinken said.

He also urged China to separate itself from Russia, a day after the G20 meeting in Bali, where Western nations criticized Russian Foreign Minister Sergey Lavrov for the operation in Ukraine, claiming that there are "no signs" Russia was ready to engage following this incident. 

Blinken said he told Wang that "this really is a moment where we all have to stand up, as we heard country after country in the G20 do to condemn the 'aggression', to demand among other things that Russia allow access to food that is stuck in Ukraine".

He added that there were "no signs" Moscow was willing to engage after it faced a barrage of criticism at the G20 talks a day earlier.

On its part, China's foreign ministry said, as the two superpowers seek to reduce tensions, the Chinese Foreign Minister Wang Yi and his US counterpart Antony Blinken on Saturday reached a "consensus" on improving ties during a G20 meeting, 

"The two sides, on the basis of reciprocity and mutual benefit, reached a consensus to promote the Sino-US joint working group consultation to achieve more results," the foreign ministry said in a readout of the meeting.

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It is worth noting that the two powers have toned down their rhetoric and increased cooperation at a time when the West's attention is focused on the Russian military operation in 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 stated when he began negotiations at a resort hotel in Bali, where the two had attended a G20 meeting the day before. "We very much look forward to a productive and constructive conversation," Blinken said.

President Xi Jinping, according to Wang, believes in cooperation, as well as "mutual respect", between the world's two major economic powers, and that "regular exchanges" between them are required.

"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.