As it watches with "cautious optimism" next week's meeting of the Nuclear Suppliers Group, Prime Minister Manmohan Singh has held high-level consultations to assess the situation and consider options available if things do not work out as desired.

Singh has been discussing with External Affairs Minister Pranab Mukherjee, National Security Adviser M K Narayanan and Atomic Energy Commission Chairman Anil Kakodkar the issue amid the hope that 45-nation grouping will give a "clean" and "unconditional" waiver.

Foreign Secretary Shivshankar Menon, who is in the US and in touch with the American officials there, is also in constant contact with Mukherjee and Kakodkar over the issue.

The NSG, which failed to arrive at a final decision on the proposed India waiver at the August 21-22 meet, will consider a revised draft at its next meeting on September 4-5.

In the revised draft of the waiver, New Delhi is expecting "minimal changes" and hopes that it will have a language and "semantics which can be sold" to the people of the country without any problems, sources said.

"We are cautiously optimistic," a source said.