Al Qaeda's North African branch received around eight million euros (10 million dollars) to free two remaining Spanish hostages it held, Malian negotiators involved in their release told AFP.
"From the beginning to end, it was overall about eight million euros that was paid to the kidnappers of the Spaniards," said the mediator, who asked not to be named.
Spanish aid workers Albert Vilalta, 35, and Roque Pascual, 50, returned home to Spain on Tuesday after being released by Al-Qaeda in the Islamic Maghreb (AQIM) following nine months in captivity.
"Yes, one can say that the Spanish government paid that amount. Even if it did not pay it all (directly), it will have to one way or another reimburse the debts of the countries, people who incurred expenses in the affair," the negotiator added.
He said it was the same with the 2008-2009 kidnapping by AQIM of the Canadian diplomat Robert Fowler, the UN special envoy to Niger, with African countries stumping up money for his release and Canada eventually reimbursing them.
"Eight million euros, that's also my figure," said a northern Malian lawmaker who was also involved in the negotiations to free the Spanish aid workers.
"That's what the operation cost the Spanish government, which didn't act like the British who didn't want to pay. The Spanish paid," he added.
British hostage Edwin Dyer was killed by AQIM in May 2009.
The Spanish newspaper El Mundo reported Tuesday, without naming its sources, that Madrid paid out nearly seven million euros to secure the release of Vilalta, Pascual and 39-year-old Alicia Gamez, who was seized along with her fellow aid workers in Mauritania in November but who was released in March following an initial ransom payment.
However, a senior Burkina Faso official who had been involved in the negotiations denied that Spain paid any ransom.
"No! No! We didn't pay any ransom.... We didn't pass along any ransom money to AQIM either," said Colonel Gilbert Diendere, the chief military advisor to President Blaise Compaore.
The Spanish government strongly denied that a ransom had been paid following the release of Gamez and made no reference to ransom payments when it announced Monday that the remaining two captives had been freed by AQIM.
AQIM said in an audio statement Monday that it released two Spanish hostages after some of its demands were met, but did no provide further details, the Spanish newspaper El Pais reported.
The mastermind of the kidnapping of the Spanish aid workers, Malian national Omar Sid'Ahmed Ould Hamma, who had been jailed in Mauritania, was released by Malian authorities to whom he had been transferred hours before the Spaniards were freed, his family told AFP.