NOUAKCHOTT, Dec 22 (Reuters) - Mauritania's ruling party secured a majority in parliament after a second round of legislative elections at the weekend boycotted by several opposition parties, the West African country's electoral commission said on Sunday.
The Union for the Republic (UPR) won 74 of the 147 seats in an expanded national assembly, with its allies holding a further 34 seats, according to figures from the commission.
Opposition groups won 37 seats, led by the Tawassoul Islamist party, with 16 legislators. Tawassoul, which was banned until 2007, has an ideology similar to that of the Muslim Brotherhood.
Two constituencies have yet to be decided following legal challenges after the first round.
The legislative vote was the first since an army putsch catapulted Mohamed Ould Abdel Aziz to power in 2008.
It was boycotted by 10 opposition parties, including the main Rally of Democratic Forces (RFD) party led by Ahmed Ould Daddah, which accused the government of rigging the vote.
Abdel Aziz won a presidential election in 2009 and is now a Western ally in fighting al Qaeda in the poor and frequently unstable Sahel region of West Africa.
In municipal polls, the UPR won 70 percent of the country's communes, including a majority in the capital Nouakchott and the main port city of Nouadhibou.
Mauritania, a country of 3.2 million people, has reserves of iron ore, copper and gold and is seeking to encourage exploration in its offshore oil and gas sector. (Reporting by Laurent Prieur; Writing by Daniel Flynn; Editing by David Brunnstrom)