The U.S. and Chinese presidents on Wednesday announced they would collaborate more closely to take action on climate change, while seeking to minimize conflicts between the two largest economies in the world.
Formal talks between U.S. President Barack Obama and his Chinese counterpart Xi Jinping in Beijing's Great Hall of the People yielded pledges on both sides to improve bilateral ties, which have been strained in recent years by allegations of cyber-espionage, growing Chinese military power in the region, and U.S. attempts to counter Beijing's influence.
Speaking to reporters after their meeting, Xi called for further cooperation with Washington on a range of issues.
"The Pacific Ocean is broad enough to accommodate the development of both China and the United States and our two countries should work together to contribute to security in Asia," Xi said.
"The two sides should respect the other's core interests and major concerns, and persist in managing differences in a constructive fashion."
Obama, who has had ample opportunity during this week's Asia Pacific Economic Cooperation (APEC) leadership summit for informal discussions with Chinese leaders, was meeting Xi formally for the first time in more than a year.
"A strong, cooperative relationship with China is at the heart of our pivot to Asia," Obama said, in a reference to his administration's renewed diplomatic initiative in the region, which has been criticized in the official Chinese media as a bid to contain China's rise as a world power.
"If the United States is going to continue to lead the world in addressing global challenges, then we have to have the second largest economy and the most populous nation on Earth as our partner," he said.
Analysts said Obama's trip to Beijing for APEC had been a valuable opportunity to mend bilateral ties for both sides.
"This shows us that both China and the United States want to do everything they can to improve relations and avoid confrontation," Joseph Cheng, politics professor at Hong Kong's City University, told RFA.
He said Obama's mention of weeks of pro-democracy protests in Hong Kong had been muted, so as to avoid antagonizing his hosts.
"Neither side wants to be at loggerheads at this point, so Obama limited his comments to supporting the fight of Hong Kong people for democracy from the point of view of universal values," Cheng said.
But Wu Fei, professor in the school of Journalism and Communication at Jinan University in the southern city of Guangzhou, said the apparent easing in ties masks conflicting military interests in the Asia Pacific region.
"If China starts building a series of military bases in the South China Sea, that's going to constitute a threat to the United States, because it will upset the balance of power between the two sides," Wu said.
"If that balance is upset, new frictions are bound to emerge," he said. "The consensus between the two sides is that they shouldn't allow such frictions to result in an overall deterioration in relations."
"I think that conflicts between the U.S. and China are still there, and are likely to intensify," Wu said. "It's just that they shouldn't be allowed to develop into confrontation."
Meanwhile, the deal announced by both leaders on curbing greenhouse emissions was welcomed by environmental groups as potentially contributing towards a United Nations goal of limiting global warming.
A U.N.-brokered attempt to win an international treaty on emissions at Copenhagen in 2009 collapsed after Washington said it wouldn't sign up to any global deal that didn't include Beijing.
Together, China and the United States account for 45 percent of total global carbon emissions.
Greenpeace East Asia senior climate and energy campaigner Li Shuo told Agence France-Presse: "I think it's a very positive signal that will have a positive impact on [future climate negotiations]."
He said China's commitment that 20 percent of its energy would come from renewable sources by 2030, would, if realized, be the equivalent of powering the entire United States from non-fossil energy sources.
But he said the deal can only be regarded as a starting point.
Jinan University's Wu said China's willingness to collaborate on climate change had likely been a surprise to U.S. officials in the wake of Copenhagen.
"Back then, Obama gave a speech at Copenhagen saying that China would need to join in on any climate deal," Wu said. "China took him seriously."
"I don't think that was Obama's intent [at the time]."
Preparing for Paris
Under the terms of the new agreement, China pledged for the first time to limit its greenhouse gas output—by setting a target of around 2030 for its emissions to peak.
Obama said the United States would cut its own emissions of greenhouse gases by 26-28 percent from 2005 levels by 2025.
The announcement is widely seen as crucial to the success of a U.N. global climate pact to be negotiated in Paris next year to limit global warming to two degrees Celsius (35.6 degrees Fahrenheit).
Beyond a two-degree rise lies a tipping point for catastrophic droughts, floods, mass extinctions and other disasters.
The rest of the world's nations will be submitting their plans for cutting greenhouse gas emissions in the first quarter of 2015, for ratification at the Paris summit.
Reported by Yang Fan for RFA's Mandarin Service, and by Wen Yuqing for the Cantonese Service. Translated and written in English by Luisetta Mudie.