Some of the European hostages were released in May
A Tuareg tribal leader asked to help negotiate the release of European tourists being held in the Sahara desert has been reporting back on his mission.
Iyad Ag Agaly arrived in Bamako, the capital of Mali, for a meeting with German and Malian officials.
The 14 hostages were taken in Algeria earlier this year and are thought to have been smuggled over the border into Mali by a militant Algerian Islamic group.
The Salafist Group for Preaching and Combat (GSPC) is reportedly asking for about $5m for each hostage.
Iyad Ag Agaly - a one-time Mali Tuareg rebel leader - had been "travelling to every corner of the desert" looking for the hostages, said Mali's Minister for Territorial Administration, Kafoungouna Kone.
Communications Minister Gaoussou Drabo confirmed that the Tuareg leader had returned to Bamako but did not give details of his visit or confirm if he had met the hostage-takers.
According to the Algerian newspaper El Watan, Mali and Germany have given the kidnappers a 48-hour ultimatum to release six of the hostages who are reported to be sick.
Diplomats told Reuters that German negotiators are refusing to pay the ransom demand, fearing it will set a dangerous precedent.
"The situation is very difficult. The demands are exorbitant," said one close diplomat to the negotiations in Mali's northern town of Gao.
"We hope that they will release the hostages soon, but my feeling is that it is going to take some time."
The hostages - nine Germans, four Swiss and one Dutch - were part of a group of 32 seized while travelling without guides in southern Algeria between February in March.
Seventeen were freed when Algerian soldiers raided the kidnappers' camp in May.
One of the hostages, a German woman, has reportedly already died from heatstroke while in captivity.