Ghana has had a stern warning from the Organisation for Economic Co-operation and Development to ensure that its emergence as a tax haven does not fuel corruption and crime in west Africa.

Ghana is becoming an offshore financial centre but Jeffrey Owens, head of the OECD's Tax Centre, said: "The last thing Africa needs is a tax haven in the centre of the African continent." Ghana wants to become a west African financial hub, taking advantage of its emergence as an oil producer. This year the first of Ghana's 3.2bn barrels will begin to flow from its waters.

The OECD is in talks with Ghana to guarantee the country "adheres to the highest standards and integrity". Owens said Ghanaian officials "are aware of the risks they are running". Barclays Bank has been advising Ghana's government on establishing its financial centre.

Wilson Prichard, a researcher at the Institute of Development Studies who has closely followed Ghana's development as an offshore centre, said: "Aside from the general social costs associated with the operation of tax havens globally, in the absence of a very strong regulatory framework and very strong standards of transparency there's a particularly high risk that a tax haven in west Africa, which is home to major oil wealth and high levels of corruption, could facilitate large-scale corruption and tax evasion, and pose a correspondingly large risk to good governance and economic growth in the region."