New Delhi : India and the US are "working hard" on taking forward their landmark civilian nuclear deal but it would be "very hard" to put a timeframe on concluding their negotiations, key American interlocutor Nicholas Burns said here Friday.
"We're working very hard, we're working very well," Burns, the under secretary of state for political affairs, told reporters on the progress to conclude the 123 agreement that will enable the resumption of nuclear commerce with India after a 30-year gap.
"It's very hard to tell…when the work will be done," he added, an indication that differences still persisted on key clauses of the 123 agreement.
Burns arrived here Thursday on a three-day visit to iron out the sticking points in the agreement ahead of a meeting in Germany next week between Indian Prime Minister Manmohan Singh and US President George Bush on the sidelines of the G-8 Summit.
Burns, who held technical level talks with officials of the external affairs ministry and the Department of Atomic Energy (DAE) Thursday, met Foreign Secretary Shivshankar Menon in the evening.
The meeting, which lasted for four hours, stretched late into the evening and included a working dinner.
Menon had visited Washington last month for talks with Burns on the 123 agreement.
Indian and US technical experts then held two-day talks in London May 21-22 during which India clarified its concepts on key issues like nuclear testing and demand for access to reprocessing technologies.
Before going in for the technical level talks Thursday, Burns had said the two countries were "nearly there" but "some hard work has to be done" before the 123 agreement could be concluded.
At the same time, he expressed confidence that the pact will be concluded and that there were a "lot of reasons to feel optimistic".
The Indian external affairs ministry is yet to react on the talks.
The talks are focusing on four key areas: reprocessing of spent fuel, the technology for reprocessing, right to continue testing and uninterrupted fuel supplies.
Officials say there are major differences between India and the US on all four issues and intensive negotiations would be required if the text of the 123 agreement is to be finalised by the time Burns leaves Saturday for the G-8 Summit.
Burns' delegation includes his chief technical negotiator Richard Stratford and Ashley Tellis, a strategic expert at the Carnegie Endowment for International Peace who had played a key role in structuring and implementing the India-US civilian nuclear deal.
The Indian delegation includes S. Jaishankar, Indian high commissioner to Singapore who has been involved in the nuclear talks earlier, and top officials of the DAE.
The talks are being held against the backdrop of statements from the Communist Party of India-Marxist (CPI-M) that supports the government from the outside and the opposition National Democratic Alliance (NDA) that parliament should be taken into confidence before the 123 agreement is announced.
Since parliament is not in session, the opposition leadership expects to be consulted before the deal is announced.
The NDA also wants assurances on two issues: that India's strategic programme remains untouched and that India retains control over its foreign policy.