NOUAKCHOTT, Nov. 7 (Xinhua) -- A partial election to replace a third of Mauritanian senators opens on Saturday in 18 constituencies in 13 provinces of the country, according to a press statement of the Interior Ministry.

The campaign for this election, which involves 18 of the 56 Senate seats including the Mauritanian African senator, came to an end on Friday midnight.

According to the observers, the ruling Republican Union (UPR) is the most favored in the election having attracted large numbers of supporters in the past weeks.

Messaoud Ould Boulkheir, House speaker and the loser of the July presidential election, has accused the government of Ould Mohamed Langhaf of interfering in electoral affairs and using his influence in favor of the ruling party.