Last June, Mauritanians voted overwhelmingly to limit the president's mandate to two five-year terms. The army officers who staged the coup, the Military Council for Justice and Development (CMJD), led by Col Ely Ould Mohammed Vall, pledged to respect this and relinquish power peacefully within two years of the transition.

The former ruling party, the Republican Party for Democracy and Renewal (PRDR), dominated the country's politics from the introduction of multi-party elections in 1992 until the August 2005 coup.

Which are the main parties taking part?

Nineteen candidates will be standing in the presidential election, of which 11 are independent and eight are representing political parties.

The opposition Coalition of the Forces for Democratic Change (CFCD), a coalition of 11 political parties, is the largest party coalition in the country after winning 41 of 95 seats in the November 2006 legislative election.

The El-Mithaq or " Convention " bloc comprising 17 political parties including the former ruling PRDR. However, the opposition CFCD sees the Convention as a smoke screen for the return of supporters of the former regime and of the ruling military officers.

Observers say support from the Islamist (Muslim Brotherhood) Centre Reformists (RC) could be decisive for the election outcome. The RC say they will back the Mauritanian Party for Unity and Change (HATEM-PMUC) which is opposed to establishing relations with Israel.

Who are the main candidates?

Ahmed Ould Daddah: Rally for Democratic Forces (RFD) leader and opposition CFCD member. A half-brother of the first Mauritanian president, Mokhtar Ould Daddah, and former trade minister, he was arrested in 1998 for allegedly saying publicly that the government had agreed to have Israeli nuclear waste buried in Mauritania. In January 2005, he was acquitted of involvement in three coup attempts between 2003 and 2004.

Mohamed Ould Maouloud: United Forces of Progress (UFP) leader and opposition CFCD member. He intends to carry out constitutional and institutional reform and wants to sever ties with Israel.

Messaoud Ould Boulkheir: People's Progressive Alliance (APP) leader and opposition CFCD member. Boulkheir is a prominent anti-slavery activist and is a Haratine (descendant of slaves). However, he claims the Haratine are Arabs. A former rural development minister, his Action of Change (AC) party was banned in 2002. He became APP leader in 2004.

Saleh Ould Mohamadou Ould Hanenna: Mauritanian Party for Unity and Change (HATEM-PMUC) leader and opposition CFCD member. A former colonel, he was dismissed from the army in 2002 and as leader of a group of army officers called the Knights of Change, he was accused of masterminding a coup attempt in June 2003 which saw him put into jail. In February 2005, he was sentenced to life imprisonment but was released by the CMJD after the August 2005 coup.

Sidi Mohamed Ould Cheikh Abdellahi: Independent candidate seen by the opposition and media as the army's candidate. He is being supported by the "Convention" coalition and the Democratic Unionist Party (UDP).

Mohamed Khouna Ould Haidalla: Independent candidate and former president from 1980 to 1984. In 2004, he was given a suspended prison sentence for his alleged involvement in the three abortive coup attempts between 2003 and 2004. He was acquitted in February 2005.

Mohamed Ahmed Ould Baba Ahmed Ould Salihi: Independent candidate. A former journalist, he promises to freeze diplomatic relations with Israel if it does not comply with UN resolutions. He also pledges to introduce the Koran to schools, colleges and universities.

How much power will the winner have?

The power and prerogatives of the future president seem to be limited by the ruling military council's strong arm. In January, Vall warned candidates against going into some sensitive issues involving the high interests of the state, such as relations with Israel and the future role of the army.

While pledging the CMJD's neutrality, Vall hinted at the possibility of intervening if no candidate obtained 50% of the expressed suffrage.

Will there be foreign observers?

Yes, some European Union observers arrived last month and observers from the African Union and Arab League are also in the country.

What are the issues?

Among the world's poorest nations, Mauritania is a largely desert country with an Arab-Berber population in the north and black Africans to the south.

The discovery and exploitation of its offshore reserves of oil and natural gas has held out the promise of increased economic prosperity for a country traditionally reliant on drought-proof agriculture and exports of fish, fish products, iron ore and gold.

Its location as a bridge between Muslim North Africa and Christian and animist black Africa places it in a delicate position.

It is one of the few Arab countries to have recognised Israel and has also cooperated in the US war against terror.

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"They asked me to give them 120 naira (almost $1) before I'd be registered but I refused," says journalist Ann Onyealisi.

The electoral officers deny the charge even though many other people at the registration point corroborated Ms Onyealisi's claims.

"They said they needed the money to buy petrol to run small electric power generators that powered the laptop they were using for the exercise."

In many registration centres across the capital city, Abuja, electoral officers struggled with excited crowds determined to have their picture and biodata recorded on a lap top and a web cam.

"I've been here for over eight hours," says Joseph Itan, 27, looking into the tiny web camera that was capturing his image onto a cheap laptop in Abuja's Maitama District.

"But I stayed because it's very important for me to register so that I can vote and to avoid being denied some privileges that are now tied to the voter card."

Public holiday

The compilation of a new voters' roll began two months ago as Africa's most populous country prepares for landmark elections that should mark the first handover of power from one civilian regime to another since independence from Britain in 1960.

The exercise has, however, been dogged by lack of public awareness and inadequate or faulty electronic registration equipment.

Some states made the voter registration mandatory for civil servants, warning that they would not receive their monthly wages if they failed to obtain voter cards.

These factors and "increased political awareness" are being cited as the reason for the higher turn-out witnessed in the final days of the exercise.

"Definitely, there's a higher political awareness among Nigerians now," says Abdulsalam Ismail as he waits to register at a centre in Maitama's OAU Quarters, Abuja.

"We've all woken from our slumber. We had to wake up because we weren't getting what we wanted and we have now realised that this vote could make the difference."

Determined

In another registration centre in Abuja's Wuse II district, two first-time voters said they were looking forward to casting their first vote.

"It's going to be my first vote because during the last elections in 2003, I wasn't yet 18," said Tunde Akanbi.

But another first-time voter, Mercy Simon, is not as determined.

"I was there yesterday to register and they gave me a number and asked me to wait for my number to be called so I could register," says Ms Simon.

"The electoral officials did not come until 1000 and by 1700, they were already packing up their equipment without registering many of us. I couldn't go back this afternoon because I'm working."

But this has not discouraged 27-year old Ben Shima who says he is determined to have a say in the forthcoming elections.

"I want to choose my leader and I believe that my vote will count," he says. "I don't even know whom I'd vote for, but I know I have to vote."

Many of the people queuing up to obtain the voter card are calling for an extension of the exercise.

Nigeria's Independent National Electoral Commission (Inec) initially said an extension of the deadline was unlikely - but they subsequently relented and are now allowing until Friday for voters to register.

"Even if we extend this registration for another three months, the same thing will happen," says Ibrahim Biu who is in charge of voter education at Inec.

Some 40,000 laptops and direct data-capturing machines were deployed for the exercise, Inec says.

The electoral body says so far, it has been able to register about 50 million of the estimated 70 million eligible voters in the country.