* MOODY'S AFFIRMS GHANA'S B3 RATING, MAINTAINS STABLE OUTLOOK?

CAPE TOWN (Reuters) - South Africa faces "tough decisions" to boost economic growth after years of stagnation, new President Cyril Ramaphosa in a State of the Nation address on Friday a day after his inauguration.

ADDIS ABABA (Reuters) - Ethiopia announced a state of emergency on Friday after Prime Minister Hailemariam Desalegn on Thursday announced his intention to step down amid unrest and a political crisis in the Horn of Africa country.

CAPE TOWN (Reuters) - South Africa faces "tough decisions" to reduce the size of its fiscal deficit and stabilise its debt after years of weak growth, President Cyril Ramaphosa said on Friday in a State of the Nation address the day after being inaugurated.

ACCRA, Feb 16 (Reuters) - The Bank of Ghana said the yield on its weekly 91-day bill dipped to 13.34 percent at an auction on Friday from 13.36 percent at the last such sale, on Feb. 9.

ABUJA (Reuters) - At least 18 people and possibly many more have been killed in a clash between bandits and villagers in northwest Nigeria, police said on Friday, and President Muhammadu Buhari ordered security forces to track down those responsible.

FREETOWN (Reuters) - Voters across Sierra Leone stayed glued to their radios and TVs deep into the night as candidates vying for the presidency of the West African nation faced off in the first ever debate to feature all the main candidates.

ADDIS ABABA (Reuters) - Ethiopia's ruling coalition has lost its authority and all parties must help map the country's future, an opposition leader said on Friday, suggesting political tensions in Africa's second most populous country are unlikely to ease soon.

CAIRO (Reuters) - Al Qaeda leader Ayman al-Zawahiri has urged Egyptians to topple their government in the second message from Islamist militants this week calling for violence in Egypt where presidential elections are due in March.

GOMA, Democratic Republic of Congo (Reuters) - Five Congolese soldiers were killed, a senior army officer said on Friday, in a clash with Rwandan forces this week that now risks inflaming tensions between two neighbours with a long history of troubled relations.

JOHANNESBURG (Reuters) - South Africa's Treasury is set to present its 2018 budget to parliament on Wednesday but market focus is on whether new President Cyril Ramaphosa will reshuffle the cabinet before then and replace Finance Minister Malusi Gigaba.

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JOHANNESBURG (Reuters) - Matshela Koko, a former acting chief executive of South Africa's sole power provider who has been at the heart of corruption allegations at the state utility, has resigned, a spokesman for Eskom said on Friday.

JOHANNESBURG (Reuters) - A South African court on Friday threw out the findings of a public anti-graft watchdog that Barclays Africa unduly benefited from an apartheid-era bailout of another bank and should repay.

JOHANNESBURG (Reuters) - Ajay Gupta, one of the three Gupta brothers under investigation over accusations of corrupt links to ousted South African president Jacob Zuma, left the country for Dubai 10 days ago, a Johannesburg airport spokeswoman said on Friday.

JOHANNESBURG (Reuters) - South Africa's new president, Cyril Ramaphosa, is expected to give more details about how he plans to tackle corruption and boost economic growth on Friday, when he delivers his first state of the nation address.

ADDIS ABABA (Reuters) - Ethiopia's ruling coalition has lost its authority and all parties should be involved in mapping the country's future, an opposition leader said on Friday, a day after the Prime Minister resigned.

NAIROBI/ACCRA, Feb 16 (Thomson Reuters Foundation) - On a recent Saturday afternoon, Joseph Njuguna received a worrying call. Without his permission, someone was excavating a small piece of land he had bought six years ago.

CAIRO (Reuters) - Egypt's state security prosecutor on Thursday remanded for questioning a former Islamist presidential candidate who was detained over alleged contacts with the banned Muslim Brotherhood, state news agency MENA said.

ADDIS ABABA (Reuters) - Ethiopia's Prime Minister Hailemariam Desalegn suddenly resigned on Thursday in what he described as a bid to smooth reforms, following years of violent unrest that threatened the ruling party's hold on Africa's second most populous nation.