It is unfair to say that OPEC is not transparent enough regarding its production and its reserves, OPEC interim general secretary Adnan Shihab-Eddin said during an oil conference here.

He was reacting to comments made by UK Chancellor Gordon Brown calling on OPEC nations to become more transparent and 'prevent high prices hurting the poor'.

Brown wants more transparency from OPEC nations about the state of the world's reserves to prevent instability and speculation in the market.

'We have always been as transparent as possible, Shihab-Eddin said, adding that the bloc publishes figures every year about its reserves and its production capacities.