Iran retains its position as the second-largest producer in the Organisation of Petroleum Exporting Countries (Opec) despite the group\'s report that Nigeria has now obtained the rank, the students news agency ISNA quoted the country\'s Opec governor Mohammad Ali Khatibi as saying. Opec\'s Annual Statistical Bulletin has put Nigeria ahead of Iran, adding that Iranian experts were examining the report. \"Opec rationing is based on production, not export, and Iran still holds the second-largest Opec producer status and no change has happened in this regard,\" said Khatibi. Khatibi said Iranian experts had found ambiguities in some of the figures in the Opec report and thus the experts \"did not confirm Nigeria\'s export increase\". \"In the report Iran\'s oil income exceeds that of Nigeria in 2010. Then how would it be possible for Nigeria\'s oil income to be less than that of Iran despite having boosted its exports?\" Khatibi said it was predictable that Venezuela would overtake Saudi Arabia since in the past two years it had taken measures to boost its reserves. Opec\'s growth in oil reserves was mainly due to Venezuela, whose holdings rose to 296.5 billion barrels from 211.2 billion in 2009, as the report said. Top Opec exporter Saudi Arabia\'s reserves were steady at 264.5 billion barrels. Iran and Iraq also boosted their reserves last year. In October, Iran increased its reserves to 150 billion barrels within a week of an upward revision by Iraq, ensuring that Tehran continued to rank above Baghdad. From / Gulf News