Seven aid workers and their guide were killed by armed men in a deadly attack in Niger, French charity ACTED said on Sunday.

The French government called it a terrorist attack, though no group has yet claimed responsibility.

Unidentified gunmen attacked the group August 9 in the Kouré region, around 50 kilometers from Niamey capital.

The victims, who are both French and Niger nationals from ACTED and IMPACT aid organizations, were "senselessly and cowardly murdered", according to ACTED, which did not give additional details about the incident.

French President Emmanuel Macron spoke to Niger President M. Mahamadou Issoufou about the incident the French call "the murderous attack that cowardly targeted a group of humanitarian workers", according to a statement from the French Presidency on Monday.

The Elysee statement said President Macron has also sent condolences and the nation's support to the victims families and that both the French and Niger presidents are working to clarify the circumstances of the attack.

"Their determination to pursue the fight against terrorists in Sahel remains intact," the statement said.

French troops and the army in Niger and neighboring Mali are fighting to suppress a jihadist insurgency, which has seen army outposts in both countries attacked by militants.

ACTED said aid workers helping with the vulnerable affected by the conflict should not be the target of attacks.

"This heinous crime must not go unpunished, nor will it distract us from our commitment to support the people of Niger," the charity said in the statement.