Rishi Sunak said on Monday he hopes to meet Chinese President Xi Jinping on the sidelines of the G20 summit, as Britain's prime minister arrived in Indonesia for the global gathering.
Sunak, who only took office three weeks ago, is due to hold formal bilateral meetings with US President Joe Biden and the leaders of Saudi Arabia, Japan and Australia.
Britain's first-ever premier of Indian descent will also meet with Indian Prime Minister Narendra Modi.
"President Xi is here and, like all the other leaders, hopefully I will have a chance to talk to him," he told UK broadcasters travelling with him.
Sunak added he was eager to discuss "how we can fix the global economy" at the summit, as well as "unequivocally condemn Russia's hostile and illegal war" in Ukraine.
He acknowledged the grouping of the top 20 world economies was "very different" from the Western-led G7, following reports the G20 will not issue a final joint statement amid divisions over Russia.
"The G20 is a very different forum to the G7," Sunak said, calling the latter "a group of like-minded liberal democracies with similar values".
"But that doesn't mean that we shouldn't be engaged in it. We should make our voices heard and constructively work with people where we can."
Earlier Monday, Biden and Xi held a three-hour summit -- a first face-to-face meeting of the two countries' leaders in more than three years -- aimed at stopping their simmering rivalry from spilling over into conflict.
- 'Challenges posed' -
Like the United States, Britain's relations with China have soured in recent years over a host of contentious issues, including Beijing's crackdown on the pro-democracy movement in Hong Kong.
In Sunak's first call with Biden the day after he replaced short-lived ex-premier Liz Truss in Downing Street on October 26, both leaders agreed to "address the challenges posed by China".
During campaigning to be UK Conservative leader over the summer, Sunak called China the "number-one threat" to domestic and global security, and proposed curbing Chinese funding and influence in British higher education.
He advocated using Britain's domestic security service, MI5, to help combat Chinese espionage and building "NATO-style" international cooperation to tackle Chinese threats in cyberspace.
Sunak also criticised China's global "belt and road" scheme for "saddling developing countries with insurmountable debt" during the months-long domestic leadership battle.
"They torture, detain and indoctrinate their own people, including in Xinjiang and Hong Kong, in contravention of their human rights," he said during one event.
"And they have continually rigged the global economy in their favour by suppressing their currency.
"Enough is enough. For too long, politicians in Britain and across the West have rolled out the red carpet and turned a blind eye to China's nefarious activity and ambitions," Sunak said, vowing a shift on "day one" of his tenure.