Beijing:
US Secretary of State Hillary Clinton arrived in Beijing on Wednesday for talks with Chinese leaders that risk being overshadowed by the case of a blind activist said to be under US protection after fleeing house arrest.
Unless it can be settled swiftly, the case of Chen Guangcheng threatens to be a major distraction at the annual two-day meeting between leaders of the world's two largest economies that starts on Thursday.
Mrs Clinton has in the past repeatedly criticised China's treatment of campaigner Chen, who riled authorities by exposing forced abortions and sterilisations under China's "one-child" policy.
US officials have kept an unusually solid wall of secrecy over Chen's case, in an indication of the sensitivity of the issue. Beijing has also refused all comment on the campaigner.
But his supporters say that he is holed up at the embassy in Beijing after escaping from his heavily guarded home on April 22.
Experts said that they saw few easy ways to resolve the case of Chen, who has said that he and his wife suffered severe beatings for defiantly speaking out after he completed a four-year jail sentence.
Forty-year-old Chen, is said to want to stay in China, but US officials would be loath to hand him over without iron-clad safety guarantees.
Kenneth Lieberthal, a China expert who was a top aide to President Bill Clinton, said he believed that the United States wanted a solution that is "the least embarrassing to China and to do so as expeditiously as possible."
"The question to my mind is whether in China this turns into a political football in a very political season. I think it's more likely to be resolved than to turn into a political football, but you never can predict this stuff," said Lieberthal, a senior fellow at the Brookings Institution.
Before the Chen case, Washington had hoped to showcase small signs of progress in relations with China at the Strategic and Economic Dialogue, which also includes US Treasury Secretary Timothy Geithner.
Largely in response to inflationary pressure, China has let its yuan appreciate. Currency levels have been a long source of friction, with US lawmakers charging that Beijing keeps the value of the yuan artificially low to flood the world with cheap exports.
On other sore points, China has in recent weeks reduced imports of oil from Iran, spoken out -- albeit cautiously -- against a rocket launch by North Korea and supported a peace plan for Syria after joining Russia in vetoing two UN resolutions.
South Sudan said that China, a major oil importer, would lend the new nation $8 billion despite Beijing's longstanding ties to Khartoum. The US pointman on Sudan, Princeton Lyman, is joining Clinton to seek China's help in ending recent fighting.