Iran's defeated candidate Ebrahim Raisi denounced numerous "violations" in the conduct of Friday's election that saw the re-election of President Hassan Rouhani, and called for an investigation.
In a letter to the Guardian Council, which oversees elections, Raisi called for "the investigation of certain violations committed before and during the election", according to the Fars news agency.
Raisi, a 56-year-old jurist and cleric, had sent hundreds of pages of documents supporting his allegations, the agency reported.
"I cannot keep quiet in the face of the injustice committed against the rights of people," Raisi said.
The conservative camp had complained of violations before polling had even closed on Friday.
Rouhani, a moderate cleric, was declared the winner on Saturday with 57 percent of the vote against 38 percent for Raisi and the complaint is not expected to invalidate the results.