The leaders of the United States and China appear to have started off on friendly terms during a weekend together in the California sun, but it remains to be seen if good vibes can bridge deep gaps.

At the aptly named Sunnylands retreat, President Barack Obama gave his counterpart Xi Jinping a redwood bench as a gift, and the leaders of the rising and established powers took a 50-minute stroll with only their interpreters.

The two sides had billed the casual summit as a way to set a positive tone after Xi became president in March. Xi will probably be in charge over a decade in which China eclipses the United States as the world’s largest economy.

While the two governments had an obvious interest in describing the summit as a success, experts said that the talks at least went smoothly - not an insignificant feat considering the number of disputes.

“Did they emerge as the best of chums? That’s hard to tell - my guess is probably not. But they understand each other and I think that’s important,” said Chris Johnson, a former CIA analyst on China who is now at the Center for Strategic and International Studies. “Both sides seemed to suggest that they can work with the other guy, and I think that’s very substantial,” he said.

But the two sides could not paper over differences on cybersecurity. Obama took China to task over alleged hacking that a recent study said has cost the US economy hundreds of billions of dollars in intellectual property theft.

The United States and China have agreed to working-level talks on cyber disputes. The issue came at an awkward time for Obama, who is under fire at home over revelations that the United States has kept broad tabs on Internet messages and phone records for purported security reasons.

Edward Snowden, the contract employee who said he leaked details of online surveillance, fled to Hong Kong. If the United States seeks his extradition, his case would present an early test on how far Xi wants to work with Obama.

In one signal of cooperation, Washington and Beijing said that they would work together to phase out hydrofluorocarbons, the mega contributors to climate change found mostly in made-in-China refrigerators and air conditioners.

The statement was not entirely new - China had agreed in April to phase out production in return for international assistance - but it went with the theme of showing that the two powers can work together.

Representative Chris Smith, a Republican from New Jersey who chairs the House foreign affairs subcommittee on human rights, voiced disappointment over the summit.

He said that Obama, who mentioned human rights in his opening statement, should have started the relationship with Xi by insisting on the release of imprisoned activists including Liu Xiaobo, the Nobel peace laureate who authored a bold petition for reforms. “Making a cursory statement about human rights just is ineffective and it’s read that way by Beijing,” Smith told AFP.

“He is talking to the jailer of a Nobel Peace Prize winner. Imagine if the Nobel Peace Prize winner was Nelson Mandela and he was meeting with the (South African) leader and doesn’t mention - demand, frankly - the release of Nelson Mandela,” Smith said. “It’s untenable, especially because he’s a Nobel Peace Prize winner himself,” he said of Obama.

Aides said that Obama and Xi spoke at length about issues that have often divided the Pacific powers, including North Korea and the rising friction between China and US ally Japan in the East China Sea. Xi, seen as more effusive and confident than his famously stiff predecessor Hu Jintao, also raised his frequent theme of creating a “new type of great power relationship.”

The slogan, if vague, is sometimes seen as his call for China and the United States to avoid the conflict that has historically plagued relations between emerging and established powers.

A. Greer Meisels of the Woodrow Wilson Center for International Scholars said the summit could be seen as successful by going off without a hitch and avoiding missteps that have clouded many previous US-China meetings.

The talks showed that the two leaders “are taking this relationship very seriously and perhaps recognising that things have been a bit of tense and a little off-kilter as of late,” she said. “But this is obviously just a first step, so whether this generates additional momentum and additional positive knock-on effects, I think it’s still a little early to tell,” she said.–AFP