ASECNA said two of its six flight information regions could be affected by the strike despite court decisions and government bans on the strike in Togo, Chad, Central African Republic, Congo and Senegal.

"ASECNA is under the threat of a strike decided by the Union of Trade Unions of Air Controllers, a clandestine organization which is not recognised by any of the member states of the agency," it said in the statement.

The 18-member states organisation manages air traffic control in an area covering 16.1 million square kilometres of airspace.

"The Niamey flight information region is expected to be impacted," ASECNA said, urging passengers to check updated flight information and so-called Notice-to-Airmen (NOTAM) it will publish on its website. It added that a Niger court decision on the legality of the strike was expected.

It added that there were also risks with the airspace controlled by the Brazzaville, Congo flight information region due to the planned strike. It gave no further details on the risks, but added that a Congo government decision was also expected.

On Thursday, a court in Senegal suspended the call to strike by air traffic controllers in Senegal and Ivory Coast, the agency said.

But Paul Francois Gomis, a leader of the striking Senegalese air traffic controllers told Reuters that they are maintaining their decision to go on strike from 0800 GMT on Friday.

Gomis said ASECNA staff are demanding better working and pay conditions. He said the Dakar airport Air traffic controllers are short-staffed with only 60 people working where 80 are really needed.

Dakar airport authorities could not be reached for comments.