The outcome of the meeting between Modi and Xi in Tashkent will determine proceedings at the two-day plenary meeting of the atomic trading club which began in Seoul today, sources said.
Though some other countries like Turkey, New Zealand and South Africa have reservations over India's membership to the 48-nation grouping, India feels their opposition will fizzle out once China takes a favourable position towards New Delhi.
China's position on India's NSG bid is very crucial, sources said.
Modi arrived here today on a two-day visit to attend the annual summit of the Shanghai Cooperation Organisation (SCO).
Earlier, Pakistan President Mamnoon Hussain met Xi on the sidelines of the summit and thanked China for supporting Pakistan's case for NSG membership.
Giving clear indication of its opposition to India's NSG bid, China yesterday had underlined the differences within NSG members, saying "parties are yet to see eye-to-eye on this issue".
While making some right noises of playing "constructive" role on the issue of memberships of India and Pakistan, China maintained that the matter was not on the agenda of the plenary. Here too, Beijing clubbed the two sub-continental neighbours despite the marked difference in their nuclear non-proliferation track record.
Coinciding with the SCO summit, the two-day annual plenary of the NSG began today in the South Korean capital during which India's application for membership of the atomic trading club is likely to be deliberated upon.
While the US and France have issued statements ahead of the plenary strongly supporting India's case and asking members to back New Delhi, China has been unrelenting in its opposition harping on the need to have a criteria for non-NPT countries like India and clubbing India's case with that of Pakistan for which it is batting.
Roughly 20 countries are backing India's case fully but given that the decisions in NSG are taken by consensus, India faces an uphill task.
India is seeking membership of NSG to enable it to trade in and export nuclear technology.