It is only the third time in OPEC’s 47-year history that such a high-level meeting has taken place. The first was in Algiers, in 1975, at the height of OPEC’s nationalist period; the second was in 2000, when the oil cartel met in Venezuela to devise a strategy to increase prices after they had collapsed to about $10 a barrel in the late 1990s.

This meeting, which lasted less than 24 hours, was supposed to focus on long-term issues like the security of supplies and environmental policy. The Saudis in particular sought to reassure the world that OPEC was a reliable oil supplier.

“OPEC has made a point, from its establishment, to work for the stability of the oil markets,” said the Saudi foreign minister, Prince Faisal, at a news conference after the close of the summit on Sunday. “Oil should be a tool of construction and development, not one of dispute.”

Saudi Arabia also wanted to highlight a new emphasis on protecting the environment by announcing the establishment of a $750 million fund to reduce carbon emissions. The kingdom will contribute $300 million for research into technology that captures carbon spewed by power plants or refineries and stores it underground. In addition, Kuwait, the United Arab Emirates, and Qatar will provide $150 million each.

Oil producers see climate policies that focus on oil consumption as an unfair way to curb the use of fossil fuels worldwide. By financing research into carbon emissions, Saudi Arabia says it is seeking ways to extend the use of petroleum resources at a time when global warming could lead to changes in consumer behavior in Western countries.

“We want to continue using fossil fuels while protecting the environment,” said Mohammad al-Sabban, a senior Saudi government adviser on climate change. “What we are worried about is for industrialized countries to use climate policy as a pretext to discriminate against oil.”

Other ministers also expressed the more moderate views that typically emerge from an OPEC meeting. Despite Mr. Ahmadinejad’s statement about oil prices being paltry, officials from several other countries — including the United Arab Emirates, Nigeria and Saudi Arabia — said that prices were too high.