Russia takes over from Britain and will chair the group for the next year.
This is the first time that Russia has held the leadership of the organization, whose other members are the United States, Britain, Canada, France, Germany, Italy, and Japan.
Russia officially joined the group as a full member in 1997.
Russian President Vladimir Putin has said he wants to use the country's G-8 presidency to boost Russia's reputation as a stable energy provider to the world's oil and gas markets.
Russia's G-8 presidency coincides with a decision by Russia's state-controlled Gazprom gas monopoly to cut back gas supplies to neighboring Ukraine over a price dispute.
The issue threatens to disrupt gas deliveries to the European Union, which receives one-quarter of its natural gas from Gazprom, primarily via Ukrainian pipelines.
Russia's G-8 presidency is scheduled to feature Russian President Vladimir Putin hosting the other leaders of the group for a summit in his hometown of St. Petersburg in July.
Russia will this year also hold the chairmanship of the Council of Europe's highest body, the Committee of Ministers. The six-month presidency runs from May to November.
An exhibition of the history of the WTO in Singapore in 1996 (courtesy photo)
Armenia: Joined on 5 February 2003.
Croatia: Joined on 30 November 2000.
Georgia: Joined on 14 June 2000.
Kyrgyzstan: Joined on 20 December 1998.
Macedonia: Joined on 4 April 2003.
Moldova: Joined on 26 July 2001.
Romania: Joined on 1 January 1995.
Countries That Are Not Yet WTO Members:
Afghanistan: Submitted its application in November 2004.
Azerbaijan: Submitted its application in June 1997.
Bosnia-Herezgovina: Submitted its application in May 1999.
Belarus: Submitted its application in September 1993.
Iran: Submitted its application in July 1996.
Iraq: Submitted its application in September 2004.
Kazakhstan: Submitted its application in January 1996.
Russia: Submitted its application in June 1993.
Serbia and Montenegro: Submitted separate applications in December 2004.
Tajikistan: Submitted its application in May 2001.
Ukraine: Submitted its application in November 1993.
Uzbekistan: Submitted its application in December 1994.
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