France paid a ransom of millions of euros to Al Qaida's north African arm for four hostages held in Niger but they were not freed, a former American ambassador to Mali has told French TV.
European governments handed over 66 million euros for hostages in seven years, according to Vikki Huddleston, US representative in Mali between 2002 and 2011.
The French money, 13 million euros, was given to Mali's government which handed some of over to Al-Qaida in the Islamic Maghreb (Aqim), Huddleston told iTélé in an interview broadcast Friday.
The current US ambassador to Mali, Mary Beth Leonard, told RFI on Friday that the US strongly supports the French offensive and had transported 661 French soldiers to the country, without asking for costs to be covered, as was originally suggested.
But the four hostages, Thierry Dol, Daniel Larribe, Pierre Legrand and Marc Féret, were not freed.
They were captured at a uranium mine in Niger in September 2010, along with a Frenchwoman, Françoise Larribe, a Madagascar national and a Togolese who were later released.
Niger's President Mahamadou Issoufou said on Sunday that they were still alive.
France has always denied paying ransom for hostages but has successfully negotiated the liberation of several of its citzens in circumstances that have not been clearly explained.
Huddleston alleges that the ransom for the Niger hostages was paid indirectly, "like all ransoms", and then handed on at least in part to "the Salafists".
She told iTélé that she had seen written "in black and white" the figure of 89 million dollars (66 million euros) paid by European governments for hostages between 2004 and 2011, adding that it ended up in Aqim's pockets, allowing them to buy weapons and make new recruits.
France is currently leading an offensive against Aqim and its allies in north Mali.
The Islamists appear not to have carried out a threat to kill the seven French hostages in their hands if French troops intervened in the region.