ABUJA - Nigeria's central bank raised its main lending rate by 50 basis points to 18.50% in a decision announced on Wednesday.

The rate decision comes after data showed earlier in the day that first-quarter growth slowed, and ahead of next week's swearing-in of Nigeria's president-elect Bola Tinubu who has promised to revive the economy and combat the rising cost of living.

Inflation has remained elevated in Africa's biggest economy, eroding savings and incomes. Last week data showed inflation quickened in April to a more than 17-year high above 22%.

(Reporting by Chijioke Ohuocha Editing by Alexander Winning)