Yields on Nigeria's benchmark 20-year bond rose 55 basis points to 12.7 percent in early Wednesday trade.

This comes after the central bank unexpectedly tightened monetary policy to curb inflation after cutting the rate only four months ago, traders said.

Bond yields rose on average above 40 basis points across maturities, traders said.

They added that the central bank was withdrawing liquidity from the banking system to enforce a new cash reserve rules and also selling treasury bills.