New York  - United Nations Secretary General Ban Ki-moon Monday called for the release of two Canadian diplomats kidnapped in Niger last December, following the release over the weekend of a local staff member who was held hostage with them.

The captors set free Soumana Mounkaila, a driver who was with former Canadian ambassador to the UN Robert Fowler and his aide Louis Guay when they were abducted on December 14, 2008, while riding in a UN vehicle.

Fowler was on an official UN mission, trying to find ways to settle a growing conflict led by Tuareg nomads against governments in Niger and Mali. Folwer and Guay are believed to be held in Niger.

Ban said they should be set free "without any further delay." He expressed his appreciation to "governments and concerned individuals around the region who are helping the release of the missing staff members." dpa