Tunisian presidential candidate Nabil Karoui is to remain in prison after an appeal was turned down on Friday, just two days ahead of the poll, his party and lawyers said.
"The court of appeal has declared it does not have jurisdiction (over the case)... and therefore it has turned down the appeal against the arrest warrant for Nabil Karoui," his Qalb Tounes party said in a statement.
"It is a decision concerning the form -- the court has refused to engage in the merits of the case," said one of his lawyers, Kamel Ben Messoud.
Nazih Souii, another of Karoui's lawyers, said "he will not be able to vote on Sunday, even though he has the right to do so".
He said that a new application for the mogul's release would be submitted shortly.
"There are no ballot boxes in prison, even if some detainees retain their civil rights," Souii added.
Media mogul Karoui, 55, was arrested on money laundering charges on August 23, but the electoral commission has allowed him to compete in the September 15 poll.
Twenty-six candidates are vying to replace Tunisia's late leader Beji Caid Essebsi, who died in July, and Karoui is considered to be a frontrunner.
Other key players include incumbent Prime Minister Youssef Chahed.
Under investigation for a complaint lodged in 2016, Karoui was arrested days before the start of campaigning, prompting accusations that the timing of his imprisonment was a manipulation of justice -- a charge vehemently denied by Chahed.
Karoui's popularity has largely been built on the back of charity projects broadcast daily on his Nessma TV channel, which authorities have banned from covering the presidential campaigns.
He was nearly removed from the race in June when parliament passed an amended electoral code that would bar any candidate who handed out "favours in cash or in kind" in the lead-up to the vote.
But Essebsi never enacted the bill, leaving the door open for Karoui to run.