India and the United States apparently failed to eliminate differences on Friday as they wound up talks to finalise a deal on the implementation of the nuclear deal. It was to have been done before President George W Bush's [Images] visit next week.

Both sides have, however, said that 'progress' has been made in the talks. "The two sides had detailed and productive discussions. There was greater clarity on the issues under discussion," Navtej Sarna, External Affairs Ministry spokesman said. "Progress has been made."

There have been two days of intense negotiations between Foreign Secretary Shyam Saran and US Under Secretary Nicholas Burns.

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"We have not reached a final agreement," an American official told PTI. "There is goodwill by both governments and a commitment by President Bush to see this deal through towards a conclusion."

After meeting Anand Sharma, Minister of State for External Affairs, Burns said, "We are working very hard on this agreement on both sides and we have some more work to do,"

Sharma said that there could be no time-frame to conclude the talks and emphasised that the nuclear agreement was 'never pegged' with the Bush visit. "When two countries hold talks, you cannot give a time frame," he said, adding, however, that there was political will to carry forward the process initiated on July 18 last year.

Noting that the two countries have been 'active' for the last 11 months, Burns said, "There have been unique negotiations, which have been very challenging."

"Both of us want to complete these negotations but there are still some differences between us and those need to be worked out," he had said on Thursday. "We simply don't know whether we will have an agreement before President Bush's visit but we are trying our best."

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