The rural Chinese activist at the centre of a diplomatic standoff between Washington and Beijing now wants to leave China with his family, a U.S. spokeswoman said.

State Department spokeswoman Victoria Nuland told reporters that U.S. officials had spoken twice on Thursday with Chen Guangcheng and also with his wife and ‘they as a family have had a change of heart about whether they want to stay in China’.

"We need to consult with them further to get a better sense of what they want to do and consider their options," Nuland said.

The blind, self-taught lawyer spent six days in the U.S. Embassy after fleeing illegal house arrest and other mistreatment in his rural town where his activism angered local officials. He emerged on Wednesday when U.S. officials said they had an agreement with Chinese officials for him to set up a new life in another province.

It's unclear whether China would be willing to negotiate further over Chen's fate. The government already has expressed anger that the U.S. harbored a Chinese activist, and China's Foreign Ministry reiterated its displeasure on Thursday, calling the affair interference in Chinese domestic matters.

The diplomatic dispute over Chen is sensitive for the Obama administration, which risks appearing soft on human rights during an election year or looking as though it rushed to resolve Chen's case ahead of strategic talks this week with China attended by Secretary of State Hillary Rodham Clinton.

After fleeing persecution by local officials and seeking refuge in the embassy, Chen left Wednesday to get treatment for a leg injury at a Beijing hospital and be reunited with his family. U.S. officials said the Chinese government had agreed to resettle him in a university town of his choice.

Chen, 40, initially said he had assurances that he would be safe in China - which is what U.S. officials said he wanted - but hours later he told The Associated Press he feared for his family's safety unless they are all spirited abroad. He also said he felt pressured to leave, both by Chinese and U.S. officials.

U.S. Ambassador Gary Locke told a news conference that he could say ‘unequivocally’ that Chen was never pressured to leave. Locke said Chen left the embassy after talking twice on the telephone with his wife, who was waiting at the hospital.

"We asked him was he ready to leave. He jumped up very excited and said 'let's go' in front of many, many witnesses," Locke said.

A senior U.S. official, who spoke on condition of anonymity because of the sensitivity of the issue, said Thursday that further contacts with Chen and his wife show that his views on what is best for them ‘may be changing’.

Among the issues that would have to be worked out if Chen leaves China is whether he would go as a visiting scholar – an indication his stay would be temporary – and whether China would let him return. The government has at times revoked the passports of dissidents abroad, rendering them stateless.

A delay in figuring out how to help Chen may also undercut the U.S. bargaining power. Pressure for a resolution would subside once Clinton leaves China on Saturday.