Ghana's power minister has resigned after failing to resolve a three-year-old electricity crisis that President John Mahama, who seeks re-election this year, had promised to fix, government sources said on Friday. Power Minister Kwabena Donkor told voters in February he would resign if the crisis was not resolved by December 31.

"The president was unhappy with his performance, particularly in handling the crisis. He has accepted the resignation and thanked him for his service," one of the sources said.

President Mahama will contest what is expected to be a close-run vote in November against opposition leader Nana Akufo-Addo. The power crisis began in the 2012 election year and the opposition New Patriotic Party says it is a sign of government mismanagement. Ghana was one of Africa's top economies but growth based on exports of gold, cocoa and oil has slowed sharply due to lower global commodities prices.

Copyright Reuters, 2016