The short period “could create huge operational pressure on banks and some traders may prematurely reject the existing currency notes once the new ones come into circulation,” Kingsley Moghalu, former deputy governor of the central bank, said by text message.

An estimated 45% of adults in Africa’s most populous country dont’ have a bank account.

Kazeem Olayiwola, 44, a commercial taxi driver in the capital, said he was concerned about the time he will have to spend in line to change the notes.

“Standing in queue for hours will cost me money that I am trying to make,“ Olayiwola said.