(CNN) Turkish President Recep Tayyip Erdogan's Justice and Development Party, known as AKP, is asking the country's election council for a redo of the mayoral election in Istanbul, the country's financial capital and its largest city.

Claiming "organized irregularities," the party has for weeks contested the results of the March 31 election, which it appears to have lost by a razor-thin margin.

"There is a clear and organized irregularity and election fraud," said AKP Deputy Chairman Ali İhsan Yavuz. "There is only one body to clear the questions. It is Supreme Election Council. Their decisions are binding for all of us."

The main opposition Republican People's Party, CHP, garnered 48.79% and the AK 48.51% of the vote, according to unofficial results. A recount requested by the AKP has ended, according to Turkish news agency Anadolu and CHP members, but the results haven't been announced.

"There isn't a tiny bit of problem in the process," said CHP candidate Ekrem İmamoglu. "Before the elections, they said Turkey has the world's most trustworthy election system. Today they shout 'there are irregularities.'"

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