The Shanghai Cooperation Organization is expected to become one of the fastest developing blocs in the world, a Foreign Ministry official said on Thursday ahead of a meeting bringing together prime ministers of SCO member states.

Premier Wen Jiabao will attend the 11th Prime Ministers' Meeting of the organization in Bishkek, Kyrgyzstan, and co-host the 17th regular meeting between Chinese and Russian prime ministers in Moscow from Dec 4 to 6.

"The SCO Prime Ministers' Meeting is held at a crucial time as members of the SCO face new challenges when the international situation becomes more complex and the risk of a world economic downturn accumulates," Vice-Minister of Foreign Affairs Cheng Guoping told reporters at a news briefing.