Ivory Coast opposition leader and former Credit Suisse chief Tidjane Thiam has been excluded from the country's final list of presidential candidates, rendering him ineligible to contest an October election, a party official said on Wednesday.

Thiam told Reuters in April he would not drop his presidential bid despite a court ruling that his name be struck from the list due to his French nationality at the time of registration.

The electoral commission's decision risks reviving tensions in a country that emerged from more than a decade of civil war in the early 2000s.

The conflict was partly fuelled by disputes over nationality and electoral eligibility.

Thiam, 62, was elected as leader of the PDCI, the main opposition party in the world's top cocoa-producing nation, in December 2023.

"My removal from the electoral roll by the Independent Electoral Commission is a sad but telling example of Ivory Coast's abandonment of democracy," Thiam said in a statement to Reuters.

"We will fight, fight for democracy and peace in our country," said Simon Doho, president of the PDCI parliamentary group.

Other prominent politicians, including former president Laurent Gbagbo and his close ally Charles Ble Goude - both acquitted on charges of crimes against humanity related to the civil war - were also ruled ineligible for the October election.

So too was former prime minister and rebel leader Guillaume Soro, who was sentenced in absentia to life in prison in 2021 on charges of plotting a coup against his former ally, President Alassane Ouattara.

Ouattara, who has served three terms, has not declared whether he'll run in the election. His ruling RHDP party is scheduled to select its candidate on June 21 and 22.

Thiam's lawyer, Mathias Chichportich, said his client had filed a complaint on Tuesday with the United Nations Human Rights Committee.

"This action seeks to compel the Ivorian state to take all necessary measures to ensure that the presidential election is held under fair, inclusive, and democratic conditions," Chichportich said.