Former Malian prime minister Cheick Modibo Diarra told AFP on Tuesday he was standing for president in the July elections.
Diarra spent just eight months at the head of the deeply-divided west African nation last year before being forced to step down.
"I am running because a great many Malian people have requested that I carry their hopes for the future of Mali," he said.
"I cannot remain indifferent to their desire. The debate will be very interesting and I don't want to run from it."
Diarra was appointed in April last year by acting head-of-state Dioncounda Traore following a military coup which unseated then president Amadou Toumani Toure and led to the fall of the country's northern cities to armed Islamists linked to Al-Qaeda.
He resigned in December under pressure from the military junta which overthrew Toure.
"I have no agenda against any individual. The future of Mali is my only concern. I have the chance to take part in the development of Mali, a country that has given me everything," he added.
Diarra was an astrophysicist of international renown before entering politics in 2011.
Fifteen political leaders have declared their candidature for the presidential elections scheduled for July 28, with a possible second round planned on August 11.
Among them are two other former prime ministers, Ibrahim Boubacar Keita and Modibo Sidibe.