Founded in 2001, the SCO comprises China, Kazakhstan, Kyrgyzstan, Russia, Tajikistan and Uzbekistan as full members, with Pakistan and India as observer states.

Nasirov said that a memorandum of obligation will be signed by India and Pakistan to obtain SCO member status.

Kyrgyzstan's Minister of Economy Arzybek Kozhoshev told Xinhua News Agency this month that after the two nations join the SCO, the total population of its members will comprise "more than half of the global population".

An annual report on the SCO released on Tuesday by leading Chinese think tanks on Eurasian studies said the first expansion of its membership should be made discreetly and cautiously.

The expansion is complicated and difficult, because it "matters to the future definition of the organization itself and its future path of development", said the report by institutes affiliated to the Chinese Academy of Social Sciences and the State Council's Development Research Center.

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