President Barack Obama is expected to lobby his Chinese counterpart Xi Jinping to support military strikes against Syria during a bilateral meeting on the sidelines of a G20 summit.
Observers said Beijing was likely to continue to side with Russia to oppose military intervention in response to allegations that Syrian president Bashar al-Assad used chemical weapons against his people.
But they expected Xi to soften the rejection to avoid hurting recent personal ties with Obama, who he met in California in June at an informal summit.
"Beijing may tell Washington that it may support a strike against Syria if the US got clear proof that chemical weapons have been used by the Syrian government," said Jia Qingguo, a professor at Peking University.
The announcement of a Xi-Obama meeting, which was made by the White House yesterday, came as Obama won the backing of US House Speaker John Boehner, the top Republican in Congress, and House Democratic leader Nancy Pelosi for military intervention in Syria.
Arriving in Stockholm for a two-day visit, Obama said the world had set "a red line" for Syria and the international community's credibility was at stake if it did not take action. "I didn't set a red line. The world set a red line," Obama said, referring to international rules banning the use of chemical weapons.
The only other G20 leader Obama is scheduled to meet on the sidelines is French President Francois Hollande, who is seeking a coalition of European nations to back a military response.
China, a veto-wielding member of the UN Security Council, has said it opposed the use of chemical weapons, but Foreign Minister Wang Yi said a political resolution was the only way out because outside military interference without UN approval would exacerbate turmoil.
Russian President Vladimir Putin said the Kremlin would not rule out allowing a military operation against Syria if evidence showed that Damascus carried out a chemical weapons attack. But he insisted that any operation without UN approval would be unsanctioned aggression.
Deputy Finance Minister Zhu Guangyao said leaders of various nations, including Obama, want to discuss global economic development and challenges with Xi.
Additional reporting by Reuters, Associated Press