Algeria has refused a French request to fly over its airspace for a military operation in Niger, state radio said late on Monday, after a July 26 coup in the West African nation that lies south of the Algerian border.
Algeria opposes any foreign military action in Niger and favours diplomacy to restore constitutional order, state radio said.
France has about 1,500 troops in Niger that were stationed there before last month's coup. It is not clear what military operation Algeria was referring to, but France has not said it would intervene militarily to overturn the military takeover.
West Africa's main regional bloc, the Economic Community of West African States (ECOWAS), said last week said it had agreed an undisclosed "D-Day" for a possible military intervention if diplomatic efforts fail - an escalation that could further destabilise a conflict-torn and impoverished region.
Algeria has repeatedly said it was against any foreign military intervention in the Sahel region fearing repercussions such as an influx of migrants into its territory, a government source familiar with the situation told Reuters.
"We are against the coup but we are against a military action that would worsen the situation in Niger and beyond in the Sahel," the source who asked not to be named told Reuters.
French authorities did not immediately reply to a request for comment.
