BAMAKO (Reuters) - The third and fourth-place finishers in the first round of Mali's presidential election declined on Thursday to endorse opposition leader Soumaila Cisse in Sunday's run-off, dealing a blow to his hopes of defeating President Ibrahim Boubacar Keita.
Keita, who is seeking a second term despite jihadist attacks and inter-ethnic violence, won the first round last month with over 41 percent of the vote. Cisse finished second with nearly 18 percent.
Cisse has alleged there was widespread fraud in the first round and has been trying to unite the other two dozen candidates behind him for the run-off.
Keita's camp denies there was fraud and the constitutional court on Wednesday upheld the results, despite challenges by Cisse, third-place finisher Aliou Diallo and fourth-placed Cheick Modibo Diarra.
But Diallo, who received 8 percent of the vote, and Diarra, who claimed over 7 percent, both encouraged their supporters to make up their own minds for the second round.
"Neither IBK (Keita) nor Soumi (Cisse) corresponds with our political ideal. I will not support one or the other. Each person who voted for me is free to vote for whom they wish," Diarra told supporters in the capital Bamako.
Diallo told his followers that it was "to Malians that I leave the responsibility of expressing themselves as they wish in the second round".
Armed attacks and other security incidents disrupted voting at about a fifth of polling places in the first round and prevented around 3 percent from opening at all, casting doubts over the legitimacy of the election.
The United Nations said last month nearly 300 Malian civilians had been killed this year in inter-communal violence, which has been stoked by local jihadi groups linked to al Qaeda and Islamic State.
(Reporting by Tiemoko Diallo and Cheick Amadou Diouara; editing by Andrew Roche)