The cracks emerged a day after the six opposition party leaders held a meeting in Ankara to discuss whom to field against Erdoğan in the May 14 polls.
Five parties endorsed Kemal Kılıçdaroğlu, a former civil servant who heads Türkiye’s main secular party, as the frontrunner in the bid to end Erdoğan’s rule.
But Meral Akşener, leader of the nationalist İYİ (Good) Party, has resisted Kılıçdaroğlu, backing instead Istanbul’s opposition mayor Ekrem İmamoğlu or Ankara’s mayor Mansur Yavaş.
“I am sorry to say that as of yesterday, the Table of Six has lost its ability to reflect the will of the nation in its decisions,” Akşener said after meeting her party delegates on March 3.
Felicity Party leader Temel Karamollaoğlu hosted Kılıçdaroğlu, Akşener, Ali Babacan of the Democracy and Progress Party (DEVA), Gültein Uysal of the Democrat Party and Ahmet Davutoğlu of the Future Party at his headquarters in the Turkish capital Ankara, where they discussed the nomination of a joint presidential candidate.
She said her party was being forced to choose Kılıçdaroğlu and added: “We will not bow to this.”
Turkey heads to an election on May 14 three months after a devastating earthquake hit several provinces and claimed more than 45,000 lives.
Erdoğan this week dismissed the speculation that the election might be postponed due to the disaster and said the vote would go ahead as planned.
The splintered political opposition has been unable to agree on a candidate for more than a year.
The opposition bloc was due to announce their joint candidate next Monday.
Akşener said her party had suggested that a united candidate should be designated based on public survey results and that either the Istanbul or Ankara mayor should be fielded.
“Our demand was rejected,” she said, seeming to shut the door on any reconciliation.
Akşener called the Istanbul and Ankara mayors to their “duty” while accusing Kılıçdaroğlu of promoting “personal ambitions” over the country’s interests.
Kılıçdaroğlu however played down any tension.
“Don’t worry,” he told reporters. “All pieces will fall into place.”