The summit concludes later Sunday with a declaration expected to assure the world of sustainable oil supplies.
Venezuelan President Hugo Chavez opened the summit with a typically fiery speech on Saturday urging the grouping to be a "geopolitical agent," which earned a gentle rebuke from his Saudi host, King Abdullah.
The leaders however appeared united in defending high oil prices, which in recent weeks have skyrocketed to record near 100-dollar levels, saying they were lower than in the 1980s when inflation was taken into account.
Chavez also issued a warning that prices could double to 200 dollars if the United States attacked Iran, the second largest OPEC producer, or launched action against Venezuela.
"If the United States was mad enough to attack Iran or aggress Venezuela again the price of a barrel of oil won't just reach 100 dollars, but even 200 dollars," warned Chavez, a fiery leftist and fiercely anti-US leader.
King Abdullah, whose country is the biggest oil exporter in