A Frenchwoman who runs an organisation for malnourished children has been kidnapped in Mali, France's foreign ministry confirmed, as French troops joined in the search for the aid worker.

Sophie Petronin was abducted in the city of Gao yesterday, the ministry said, adding that French and Malian authorities were working together "to find and free our compatriot as quickly as possible".

Ms Petronin is the director of a non-governmental organisation that helps children suffering from malnutrition, the ministry said, adding that officials were in contact with her family.

Malian officials had reported the kidnapping of a woman with dual French and Swiss nationality in Gao, but the Swiss foreign ministry said today there was no indication that Ms Petronin held Swiss citizenship.

Ms Petronin, who is in her 60s, had been working in Gao for a long time as head of the NGO she started.

According to French media, she is a doctor specialising in nutrition and tropical diseases who had escaped a kidnapping by Islamists in Gao in 2012.

Northern Mali fell to jihadist groups linked to al-Qaeda from March 2012. These forces were driven out of key towns by a French-led military intervention the following year.