UNITED NATIONS - A UN driver kidnapped with two Canadian diplomats in Niger late last year has been released unharmed after several governments in the region intervened, UN officials said Monday.

Soumana Mounkaila, who is employed by the UN Development Program, was released in Mali's capital, Bamako, over the weekend, they said.

Mounkaila, a citizen of Niger, was kidnapped along with the UN Special Envoy for Niger, Robert Fowler, and Fowler's aide, Louis Guay, on Dec. 14.

Secretary General Ban Ki-moon issued a statement Monday praising the co-operation of local governments and individuals whose negotiations helped Mounkaila gain his freedom.

Ban again called on the kidnappers to free the two Canadians.

"The secretary general renews his call on those holding Robert Fowler and Louis Guay to release them both without any further delay," his spokesperson said.

In Ottawa, Foreign Affairs spokesperson Lisa Monette confirmed the driver's release, calling it "wonderful news."

But she said officials were concerned for the lives of the two diplomats.

"Our officials continue to work both urgently and closely with our partners to secure the release of Mr. Fowler and Mr. Guay."

Al Qaeda's North Africa branch has claimed it is holding the two Canadians along with four European tourists kidnapped in January.

But Niger's President Mamadou Tandja has blamed Fowler's abduction on a rebel group from the northern Niger ethnic minority of Tuareg nomads who are battling the government.

Tuareg rebels from the Front For Forces of Redress retracted their initial statement claiming responsibility for the kidnapping, saying their website had been hacked.

But some western intelligence officials believe the Tuaregs may have traded the hostages to al Qaeda.

-- With files from The Canadian Press