Turkey's electoral authorities on Wednesday ordered recounts of votes in 18 of Istanbul's 39 districts following objections over the local elections from the country's ruling party, Anadolu news agency said.
In three districts all of the votes are being recounted, while in 15 districts only votes that had been declared invalid will be recounted.
The Justice and Development Party (AKP) said the results had been impacted by invalid votes and voting irregularities.
Ekrem Imamoglu, the opposition Republican People's Party (CHP) candidate in Istanbul's mayoral election – which is separate from the local elections – asked the electoral authorities to declare him the winner, arguing the end result was unlikely to change, despite protests.
"We want justice. We demand our mandate from the YSK" – the electoral authority – "which has given the numbers, as the elected mayor of this city... The world is watching us, the world is watching this city's elections," he told reporters.
"Three or four people acting like children who had their toys taken away should not damage this country's reputation through their own internal fights."
The head of Turkey's electoral authority Sadi Guven said the recount would focus on invalid votes. He said the appeals to the electoral commission are ongoing.
The AKP alleged voter fraud in Sunday's local elections after they appeared to lose Istanbul, a traditional party stronghold.
They submitted objections to the results in all 39 districts of Turkey's largest city and in the country's capital Ankara where they also lost control.
Both the AKP and the opposition initially claimed victory in Istanbul when the results were announced on Monday, but both party's candidates have since conceded that the CHP candidate was ahead.
While it was a local election, the vote was seen as a referendum on President Recep Tayyip Erdogan's record and could complicate his efforts to combat a struggling economy.