Moise Katumbi, a businessman and former governor in the Democratic Republic of Congo, announced Friday he will stand in the country's presidential election in December 2023.
His announcement came against a backdrop of violence in the country's east after fighting resumed on Friday between M23 rebels and rival armed groups after 10 days of relative calm.
In the DRC, the presidential poll is held at the same time as parliamentary, provincial and local elections.
The president-elect would then take office in January 2024.
President Felix Tshisekedi came to power in January 2019, succeeding Joseph Kabila after 18 turbulent years as leader.
It was the country's first peaceful handover of power.
He has already announced his intention to run for a second term, despite clashes over the results.
Other possible contenders could include Martin Fayulu, the runner-up in the 2018 presidential polls who claims he was deprived of a victory in the vote.
Augustin Matata Ponyo, another ex-premier, has said he will run.
Tshisekedi's inauguration ceremony in 2019 capped more than two years of turmoil sparked by Kabila's refusal to step down when he reached the constitutional limit on his term in office.
The last two presidential elections before that, in 2006 and 2011 -- both won by Kabila -- were marred by bloodshed and dozens died in a crackdown on protests after he chose to remain in office in 2016.
A country the size of continental western Europe, the former Belgian colony lived through two regional wars in 1996-97 and 1998-2003.
M23 rebels, a mostly Congolese Tutsi group, resumed fighting in late 2021 after accusing the DRC of having failed to honour an agreement to integrate its fighters into the army.