Moreover, the chances are growing that the majority in favour of indefinite extension will be more than just the slim one some were predicting a few days ago. And for the first time, some diplomats are suggesting that a consensus in its favour may yet coalesce at the eleventh hour.
The proposal to give permanence to the NPT, widely recognised as having underpinned the reversal of the nuclear arms race, technically needs only a majority of one of the 179 signatory states for approval. Without a convincing level of support, however, the treaty could lose its moral force.
To ensure that margin, the five declared nuclear states, the United States, Russia, Britain, France and China, are preparing to offer various concessions, based on proposals from South Africa. They include a commitment to an automatic five-yearly review of their progress towards disarmament.
Other offerings from the five are likely to include pledges to complete negotiations for a comprehensive test ban by the end of next year and for the ending of all production of fissile materials for weapons use. But there seems no prospect of them agreeing to demands made by countries including Switzerland and Sweden, that they set a timetable for progress towards complete elimination of their nuclear arsenals.
A strikingly upbeat assessment of the New York conference, which is due to last four weeks and conclude on 12 May, was offered yesterday by the head of the British delegation, Sir Michael Weston. Confirming that he believes permanent extension is now secure, he said: "I think everybody agrees that it is, including some of those who don't like it."
Sir Michael went further, however, to hold out the hope that with the introduction of the concessions, unanimity may not be beyond the conference's reach. "There is a good chance that we will have consensus on indefinite extension in the end," he said. He calculated that there remained a core of only 15 states clearly opposed to indefinite extension and predicted even that number would come down.
The Campaign for the Non-Proliferation Treaty, which monitors the conference day by day, said yesterday it had counted 103 states firmly in favour of indefinite extension, up six from the day before, with another 28 leaning favourably towards it. That points to a majority of at least 130, while anything above 90 states would be enough for approval.
But Eva Cohen, a spokesperson for the campaign, warned that feelings remained strong among non-aligned countries that the nuclear powers should be pressured to move faster towards complete disarmament, as required under the original treaty. Some of these states argue that the NPT should be rolled over only for 25 years. Leading the opposition to permanent extension are Iran, Libya, Nigeria, Egypt and Indonesia.