Media reports say Turkiye’s main opposition party has claimed big election victories in the main cities of Istanbul and Ankara.

The results are reportedly a significant blow for Recep Tayyip Erdogan, who had hoped to regain control of the cities less than a year after he claimed a third term as president.

The BBC says Erdogan led the campaign to win in Istanbul, where he grew up and became mayor, but Ekrem Imamoglu, who first won the city in 2019, scored a second victory for the secular opposition CHP.

Mr. Erdogan had vowed a new era in Turkiye’s megacity of almost 16 million people, but the incumbent mayor of Istanbul secured more than 50% of the vote, defeating the president's AK Party candidate by more than 11 points and almost one million votes.

This was also the first time since Mr. Erdogan came to power 21 years ago that his party was defeated across the country at the ballot box.

In the capital Ankara, opposition mayor Mansour Yavas was so far ahead of his rival on 60% that he declared victory when fewer than half the votes were in.  Supporters blocked all the main roads in the city, waving flags and sounding their car horns.

The CHP -- the Republican People's Party – reportedly won again in Izmir, Adana and the resort of Antalya.  Significantly it also gained control of Turkiye's fourth-biggest city Bursa and Balikesir in the north-west, as well as Adiyaman, which hit hard by last year's double earthquake in the south-east.

The BBC says President Erdogan, 70, acknowledged the election had not gone as he had hoped, but he told supporters in Ankara it would mark "not an end for us but rather a turning point".

He has always relied on the "people's will" for his authority and he told supporters he would respect the electorate now too.

Political scientist Berk Esen reportedly said the opposition CHP had delivered the “biggest election defeat of Erdogan's career” and come up with its best results since 1977.

The outcome was a big success for the chairman of the CHP, Ozgur Ozel, who praised voters for deciding to change the face of Turkey in a historic vote: “They want to open the door to a new political climate in our country.”

In many parts of the world, local elections take place to select office-holders in local government, such as mayors and councilors.  Elections to positions within a city or town are often known as “municipal elections”.  Their form and conduct vary widely across jurisdictions.

In Turkiye, local elections took place on 31 March 2024 throughout the country's 81 provinces.  A total of 30 metropolitan and 1,363 district municipal mayors, alongside 1,282 provincial and 21,001 municipal councilors were elected, in addition to numerous local non-partisan positions such as neighborhood representatives (muhtars) and elderly people's councils.