Indian Foreign Minister Pranab Mukherjee's statement re-affirming New Delhi's commitment to a "voluntary moratorium" on future testing was praised as "very significant" by the Nuclear Suppliers' Group and seemed to have generated a "positive momentum" among its 45 members meeting to decide on an unprecedented waiver for India.
The waiver will allow commerce between India and the NSG, the cartel that controls global supply of nuclear fuel, reactors and technologies.
"This is a very significant statement which was discussed by members of the NSG and praised and welcomed by those in attendance," US Assistant Secretary for Arms Control and International Security Affairs John Rood told reporters at the end of the of Friday's morning session of the NSG.
He added: "On the basis of this a positive momentum has been generated in the discussion and as I said before we remain committed to achieving the objective and remain optimistic that we can achieve that."
It was not clear though whether the minister's statement will be successful in convincing sceptics like Ireland and New Zealand -two members of the NSG who are totally opposed to a "clean waiver"for India.
These countries, which were also supported by Austria and Switzerland, have been insisting that provisions be included in the draft on the proposed waiver that will allow NSG to terminate nuclear business with India if it conducted another test.
"We remain committed to a voluntary, unilateral moratorium on nuclear testing. We do not subscribe to any arms race, including a nuclear arms race," Mukherjee said in his statement issued in New Delhi before the NSG met for the second day in Vienna.
The minister's statement and the existing guideline in the NSG that provides for termination of commerce with a country that violates the rules and conducts a test were highlighted during Friday's discussions among the members to convince the sceptics who are opposed to a "clean waiver" for India.
But till the time the NSG members broke for lunch after an hour's discussion in the morning, there were no clear indications to say whether Ireland, New Zealand, Austria and Switzerland were convinced that the provisions and the statements were strong enough to ensure India keeps its commitment on no further tests.
Friday is the concluding day of the special session of the NSG that begun in Vienna on Thursday. There is pressure on the US - since it had written the draft for the India-specific waiver from the NSG - to ensure an agreement is reached by this evening.
All decisions in the NSG are taken by consensus and therefore the support of all 45 members on the proposed waiver is required.
India has made it clear that it wants a "clean waiver" and will not accept any "prescriptive conditionalities" that infringes with its sovereign rights.
But if the four countries continue to oppose a waiver without conditions, an agreement will yet again elude the NSG. It failed to reach an agreement at its last meeting on Aug 21.