ISTANBUL, July 10 (Xinhua) -- Secretary-General Mohammed Barkindo of the Organization of the Petroleum Exporting Countries (OPEC) said Sunday that the member states of the bloc support the stance of the G20 leaders who have pledged to fully implement the Paris Agreement.

　　Despite U.S. withdrawal, the other 19 members of the G20 unanimously said the climate change deal is "irreversible" and OPEC supports this position, Barkindo said on the sidelines of the World Petroleum Congress.

　　All OPEC member countries have signed the agreement, he said.

　　The 22nd World Petroleum Congress, the largest gathering for the oil and gas industry, kicked off Sunday in Istanbul with a view to addressing the challenges facing the sector.

　　"The challenges in the petroleum sector have been growing as the world population has been increasing," Jozsef Laszlo Toth, president of the World Petroleum Council, said at the opening ceremony.

　　In a declaration issued after the conclusion of the G20 summit in Hamburg, world leaders said that they remain "collectively committed" to mitigating greenhouse gas emissions but "take note of" the decision of the United States to withdraw from the agreement.

　　The Paris Agreement aims to tackle climate change by cutting greenhouse gas emissions and sets a global target of keeping the rise in the average temperature no higher than 2 degrees Celsius above pre-industrial levels.