The top United Nations human rights official has welcomed changes to Senegal's constitution to make it possible for national courts to try crimes against humanity, paving the way for former Chadian leader Hissène Habré to be tried for alleged crimes committed during the 1980s.

Mr. Habré ruled Chad from 1982 to 1990, when he was overthrown and went into exile in Senegal, where he has lived ever since.

Senegal's National Assembly adopted the latest amendment to the constitution on Tuesday, which together with previous changes allows the country's legal system to deal with such cases.

High Commissioner for Human Rights Louise Arbour welcomed the move as "a very positive development in the struggle to strengthen accountability and an important step forward in the never-ending fight against impunity."

A statement issued by her office in Geneva added that "it is rare for one State to take measures to enable the prosecution of a former head of State of another country - and Senegal should be commended for its leadership in this regard."

During Mr. Habré's rule, thousands of Chadians were allegedly tortured, and unlawful killings and other serious human rights violations took place. He was charged in February 2000 by a lower court in Dakar, the Senegalese capital, but an appeals court later ruled that Senegalese courts did not have the legal competence to try such cases if they were perpetrated in another country.

Ms. Arbour expressed the hoped that with the latest amendment, the final obstacles have been cleared and that Mr. Habré will be go on trial very soon.