The National Democratic Institute was one of the leading groups of election observers who validated President Abdallahi's 2007 election.

VOA: standard.2009.03.29

General Aziz came to power last August in a coup that toppled the country's first freely-elected leader, Sidi Ould Cheikh Abdallahi.

VOA: standard.2009.03.29

President Abdallahi says he will not take part in that vote and is urging his supporters to boycott the ballot.

VOA: standard.2009.03.29

The government says Mr Abdallahi is now free to travel and make speeches.

BBC: Mauritania frees deposed leader

Mr Abdallahi gained most votes in the first round two weeks ago but failed to get the 50% needed for victory.

BBC: Sidi Ould Cheikh Abdallahi

France and the US had cancelled their aid, pending Mr Abdallahi's release.

BBC: Mauritania frees deposed leader