ABUJA - Nigeria's naira fell on the black market, traders said on Wednesday, despite measures by the central bank to narrow the gap between the official and parallel market rates.

The naira was quoted at 900 to the U.S. dollar on abokiFX that publishes an online black market exchange rate, compared with 860 on Tuesday. The unit was quoted at 784.99 naira on the official market at 1438 GMT.

The currency gained sharply on the black market on Aug 17 after the central bank flagged new measures that capped FX transactions carried out by bureau de change outlets, limiting the spread on buying and selling to between -2.5% and 2.5% of the weighted average rate of the previous day.

The currency of Africa's top oil producer has since been weakening on the black market as unmet seasonal demand in the official window continues to spill into the informal market.

A renewed loss of confidence in the naira currency by Nigerians has also helped widen the spread between the two rates.

Olawale Edun, Nigeria's finance and coordinating minister for the economy, earlier in the month said the weaker black market rate was not backed up by economic fundamentals and that a more appropriate exchange rate would be around 700 to the dollar.

(Reporting by Elisha Bala-Gbogbo; editing by Christina Fincher)