China said Friday that blind activist Chen Guangcheng can apply to study abroad, offering a possible resolution to a crisis that erupted when he escaped house arrest and fled to the US embassy.

The apparent concession came after Chen said he was in "great danger" and urged China's government to honour guarantees on his safety, and after he phoned US lawmakers in a dramatic appeal for help to leave the country.

Chen, a campaigning lawyer who exposed forced abortions and sterilisations under the "one-child" policy, unleashed a diplomatic furore when he sought sanctuary at the embassy where he spent six days.

US officials said Chen, 40, left Wednesday after Beijing pledged he and his family would be treated "humanely", but since then he has said he feels abandoned and fears retribution by Chinese authorities.

"I am in great danger... I hope the government will respect the commitments to guarantee my rights agreed to between China and the United States," he told AFP by telephone from the hospital where he is being treated.

China has reacted angrily to the case, demanding a US apology for "interference" in its affairs. But in an announcement that opened the door to a face-saving resolution, the foreign ministry said Chen could apply to leave.

"If he wants to study abroad, as a Chinese citizen, he can apply through normal channels in accordance with the law," foreign ministry spokesman Liu Weimin said in a statement.

The comment came as the United States held new talks with Chen to try to establish the next move for the activist, who has said he does not want to go into permanent exile but is seeking a period of rest abroad.

A US diplomat spoke to Chen by phone at the hospital where he is being treated for injuries sustained in his escape, and also met his wife, according to a US official who spoke on condition of anonymity.

Jean-Pierre Cabestan, politics professor at the Hong Kong Baptist University, said it was likely the activist would be allowed to leave China.

"The Obama administration is putting a lot of pressure on the Chinese to make sure this story will end up nicely for Chen Guangcheng," he said. "I think the (Chinese) foreign ministry is going to arrange a deal."

Chen told AFP earlier he was concerned security personnel surrounding the hospital were preventing US diplomats from meeting him.

Deputy chief of mission Robert Wang was seen Friday arriving with bags of what appeared to be supplies, but was asked to leave them at the entrance. It was not clear if he was later allowed access.

The United States has scrambled to contain the growing diplomatic row over Chen which erupted days before US Secretary of State Hillary Clinton arrived in Beijing on previously scheduled talks.

In extraordinary scenes on Capitol Hill, Chen phoned in to a congressional hearing on his case Thursday to ask lawmakers for help to travel to the United States and appealed directly to Clinton.

"I really am fearing for my family members' lives," he said, speaking through a mobile phone held up to the hearing.

"The thing I'm most concerned with now is the safety of my mother and my brother," he told the hearing, as stunned witnesses and reporters looked on. "I really want to know what's going on with them."

Details of how Chen gained entry to the embassy and the circumstances of his departure have been unclear, but The New York Times gave a gripping account of a flight to safety that included a car chase through Beijing.

It said that Chen made his way to the capital where friends had arranged a rendezvous with US officials after hauling himself over walls to escape house arrest.

With Chinese security closing on on them, Chen was pulled into the American vehicle which threw off the tail and headed for the embassy where the activist was secreted in a US Marine dormitory.

Chen, a self-taught lawyer, has since said he felt pressured to leave the embassy, fearing for the safety of his family who suffered repeated abuses at the hands of local officials in their hometown in eastern Shandong province.

Rights activists said Friday that Chinese police have also detained Chen's supporters at the hospital where he is being treated, and have beaten two of them.

US State Department officials have been adamant that Chen never requested asylum and strongly denied allegations that he was pressured to leave.

Chen's flight came despite round-the-clock surveillance at his house in Shandong, where he has been under heavy restrictions after completing a four-year jail term in 2010.

At Friday's closing of the two-day Strategic and Economic Dialogue in Beijing, Clinton alluded to Chen's case as she called on all nations to uphold human rights.

"We cannot ignore our areas of difference in the comprehensive relationship that we are building," she said in an appearance with Chinese leaders.