Mauritanians are voting for the first time since the country gained independence from France in 1960.
The 62-year-old is standing down after serving the maximum two five-year elected terms.
However the status quo is likely to prevail when a new leader is elected.
Abdel Aziz has expressed his support for Mohamed Ould Ghazouani, who is a former general and defense minister.
Bangladesh elects ruling party veteran Alamgir as president
Bangladeshi lawmakers elected veteran Bangladesh Nationalist Party (BNP) leader Mirza Fakhrul Islam Alamgir as the country's new president on Thursday, making the longtime opposition figure the head of state after his party came to power in a major political transition.
Russian strikes kill 16 in Ukraine's Kyiv
Russian strikes have killed 16 people and injured more than 40 in Kyiv and the surrounding region on Thursday as President Volodymyr Zelenskyy said a failure by Ukraine's allies to replenish its stock of air defence missiles was costing lives.
Prince Harry and Meghan to move back to Britain
Prince Harry and his wife Meghan plan to move back to Britain this month, six years after they stepped down from their royal duties and relocated to the US, a source close to the couple said.
North Korea launches 10 ballistic missiles as US-South Korea drills near end
South Korea's presidential office has condemned North Korea's launch of more than 10 short-range ballistic missiles on Thursday and ordered its military to maintain full readiness during ongoing joint exercises with the United States.
Kenya tourist helicopter crash kills seven
Seven people, including five Americans, were killed on Wednesday when the tourist helicopter they were flying in crashed in Kenya's Samburu county.
6:00pm - 7:00pm
An extra hour of the UAE's biggest radio show for your drive home.
Hate That I Made You Love Me
Ariana Grande
Without Me
Halsey
Mi Chico
Dj Goja & Jason Derulo & Melody