A Mali court has dropped a case against ex-prime minister Boubou Cisse alleging he plotted to overthrow an interim government installed after last year's coup, lawyers said on Tuesday.

Cisse served under president Ibrahim Boubacar Keita, who was overthrown by army officers on August 18 after weeks of protests fuelled by frustration over his failure to tackle perceived corruption and a jihadist insurgency.

The court in the conflict-ridden Sahel state made the decision behind closed doors, according to Cisse's lawyer Kassoum Tapo, who added that it had also dropped charges against six other people.

Zana Kone, another lawyer involved with the case, confirmed to AFP that the case had been discontinued.

In late December, a public prosecutor charged six prominent figures with "conspiracy against the government" and insulting the head of state, among other things.

The military officers who staged the coup handed power to an interim government, which is meant to rule for 18 months before holding elections, after international pressure.

But many Malians are disenchanted with the interim government, which is dominated by army figures -- including coup leader Colonel Assimi Goita, currently serving as interim vice president.

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