The two leading contenders for Istanbul mayor faced off in a political debate Sunday, a week before the city is set to hold a repeat of the election an opposition candidate won and Turkey's governing party successfully challenged.

Ruling party favorite Binali Yildirim and secular opposition candidate Ekrem Imamoglu argued during the live televised debate, a rarity in Turkey, over the election authority's decision to void the first mayoral election. Yildirim, a former Turkish prime minister, said the March 31 election had been "stolen" from him.

Imamoglu, a former district mayor backed by the Republican People's Party, or CHP, narrowly won the race. He called Yildrim's claim "slanderous" and said he was the "elected mayor" who had been "cheated of rights."

Istanbul's mayoral candidate Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, accompanied by his wife, name not given, arrives for a televised debate with Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, ahead of the June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Istanbul's mayoral candidate Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, accompanied by his wife, name not given, arrives for a televised debate with Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, ahead of the June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Yildirim said the ruling Justice and Development Party, or AKP, did not want to have the election repeated when it challenge the outcome. He claimed the rerun could have been avoided if there had been a full recount of all votes. The election authority's voided the vote came after weeks of partial recounts.

Fox TV journalist Ismail Kucukkaya moderated the debate, a job that entailed managing heated moments such as when Yildirim repeatedly broke a debate rule of not talking over or directly responding to his opponent.

Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and Deniz Baykal, the then-leader of the CHP, took place before a 2002. The AKP has been in power since. Erdogan is Turkey's president.

Istanbul's mayoral candidate Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, waves as he arrives for a televised debate with Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, ahead of June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Istanbul's mayoral candidate Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, waves as he arrives for a televised debate with Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, ahead of June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Erdogan, who began his rise to political power as Istanbul's mayor, downplayed the importance of the repeat mayoral election earlier Sunday.

Noting that his party held 25 of Istanbul's 39 districts and a majority in the city assembly, the president said the June 23 vote "is just for mayor, meaning only a change in the shop window."

Erdogan also questioned international media coverage of the Istanbul election, asking why journalists were interested in the local race.

Istanbul's mayoral candidate Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, accompanied by his wife, name not given, arrives for a televised debate with Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, ahead of the June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Istanbul's mayoral candidate Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, accompanied by his wife, name not given, arrives for a televised debate with Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, ahead of the June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Istanbul's mayoral candidate Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, waves as he arrives for a televised debate with Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, ahead of June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)

Istanbul's mayoral candidate Binali Yildirim, of Turkey's ruling Justice and Development Party, or AKP, waves as he arrives for a televised debate with Ekrem Imamoglu, candidate of the secular opposition Republican People's Party, or CHP, ahead of June 23 re-run of Istanbul elections, Sunday, June 16, 2019. Televised election debates are uncommon in Turkey. The last one, between AKP leader Recep Tayyip Erdogan and the then-leader of the CHP, took place before a 2002. The AKP has been in power since. (AP PhotoEmrah Gurel)