Almost 200 Nigerian troops are due to arrive in Mali to help fight Islamist insurgents in the country's north.
It is the first West African contingent to join France's anti-rebel operation launched in Mali last Friday, the BBC reports.
In total, 3300 regional troops will be deployed in the conflict under a United Nations Security Council resolution.
Chad has confirmed it will send 2000 troops.
Meanwhile, French and Malian forces have started their first major ground operation.
Sources say street battles broke out between soldiers and rebels in the town of Diabaly, 350km north of the capital Bamako, after it was captured by rebels on Monday.
French war planes have attacked rebel positions in Diabaly and Admiral Edouard Guillaud said on Wednesday that ground operations had begun.
French Defence Minister Jean-Yves Le Drian said he expects progress to be difficult and that the central town of Konna had not been recaptured by government forces as earlier reported.
A BBC correspondent said the French and their allies need to take control of Konna and Diabaly if their campaign is to advance.
