The trial of Mauritania's leading opposition politician, Mohamed Khouna Ould Haidallah, on charges of plotting to overthrow the government begins Monday.

Opposition candidate Mohamed Khouna Ould Haidallah and 15 of his supporters face charges of plotting a coup during Mauritania's presidential election earlier this month.

The spokesman for the team of defense lawyers, Ibrahim Ould Ebeti, has expressed concern about the fairness of the trial.

Mr. Ebeti said he hopes the trial would respect the principles of the law and the presumption of innocence.

Mr. Haidallah is a former army general, who came to power after a coup in 1979. He, in turn, was ousted five years later by current President Maaouiya Ould Taya.

Security forces searched Mr. Haidallah's house before the election and found weapons that, they say, were to be used in overthrowing the government. They say they also have documentary evidence of a seditious plot.

Mr. Haidallah's aides deny the accusations, and accuse the government of rigging the election to return President Taya to power for another six-year term.

Professor Sheikh Saad Bouh Kamara, is a human rights activist, who was blocked from monitoring the elections by the government.

He was asked if Mauritania's election was free and fair.

"No, I cannot say that. The will of the population is that they want a change," he said.

President Taya narrowly survived an attempted coup in June, which was put down after two days of fighting.