The European Commission has been told to tighten up its administration of the European Union's olive oil production aid scheme, which has been attacked for leaching millions of Euro's from the EU's coffers.Brussels' financial watchdog, the Court of Auditors, has criticised the Euro 2 billion-a-year scheme, saying its audit revealed that "after thirty years of operation, and despite several changes to rules, an adequately efficient and reliable system for the management and control of the scheme has still not been achieved."It found that subsidies had neither been tied effectively to the market price of olives, nor the actual yield of the crop grown by the 2.2 million producers using the system. Subsidised surpluses have been the result, which are likely to be challenged at the WTO round on agricultural goods that was launched this year.To create market stability, the court has recommend that the Commission focuses spot checks on 11,000 sample olive oil mills to measure production levels. It has also recommended that it refuses to accept any further delays to the compilation of national surveys on olive oil production.Meanwhile, the court urged the Commission to press for the repayment of all moneys owed by producers to their national governments, because of irregular claims for EU olive oil consumption aid, under a system that was abolished in 1998.