Nigeria's four main opposition movements announced a merger, posing the sternest threat in years to President Goodluck Jonathan's ruling party ahead of elections in 2015.
Supporters said the new All Progressive Congress (APC) - made up of four regional parties - was the most significant effort to date to form a national opposition group in a country riven by geographic rivalries and an Islamist insurgency.
Past attempts at opposition alliances have fallen apart amid infighting and analysts said that judging by past form, the new party might struggle to agree on a single presidential candidate for the vote. - (Reuters)