A court in the Maldives has set aside the conviction and 15-year prison term given the former vice president on allegations he conspired to assassinate former President Yameen Abdul Gayoom.

The High Court on Monday annulled the Criminal Court's conviction of Ahmed Adeeb and ordered a new investigation.

Adeeb has been serving a combined 33 years in prison after being convicted of corruption and causing an explosion on Yameen's speedboat in 2015 in an alleged assassination attempt. With the court decision, his prison term was reduced to 18 years.

Adeeb, previously a confidante of Yameen, was arrested after the blast on the boat injured Yameen's wife.

The U.S. FBI said it found no evidence of explosives on the boat.