The debate over traffic congestion in Türkiye's most populated city, Istanbul, revived following recent comments by President Recep Tayyip Erdoğan suggesting an "Istanbul entry fee" similar to the system in London, an idea he had once considered while serving as the mayor of Istanbul Metropolitan Municipality (IBB).

"There has to be a cost for entering Istanbul. Look, you cannot enter London! There are certain rules in London," the president noted and drew attention to the traffic congestion charge system implemented in the U.K. capital.

According to research conducted by the Sabah newspaper, the fare system implemented throughout almost all of London has led residents to use more public transport. The switch has led to a reduction in urban traffic density and air pollution.

In London, various factors such as whether the vehicle is gasoline or diesel, old or new, and whether the driver of the vehicle resides in the region, impact the charges levied. Between 7 a.m.-6 p.m. on weekdays and 12 p.m.-6 p.m. on weekends and on public holidays, a fee of 15 pounds ($18.30) per day is charged in the "congestion" zone.

The fee works like the bridge tolls in Türkiye, with electronic cameras tracking license plates and thereby issuing fees to drivers – with public transportation exempted.

Using the mentioned system, it is said that the traffic density dropped by 30% in districts of the U.K.’s capital where it was implemented.

Low and Ultra Low Emission Zones are also allocated in London. Motor vehicles over a certain age pay an additional "pollution tax" to combat air pollution. It also costs twice as much to get into central London for drivers who drive old cars. It is stated that the air quality in the city has improved with the policy, which was put into practice six years ago.

Meanwhile, both locals and visitors in Istanbul, Türkiye’s most populous city with around 16 million residents, are faced with a significant issue of traffic congestion. While the city experienced temporary relief from the traffic issue during the coronavirus pandemic when fewer vehicles were on the roads, the situation worsened in the three years that followed.

According to several reports, including the one compiled by TomTom in 2021, the Turkish city topped the list of the cities with the worst traffic congestion.

An annual report by an automotive navigation system producer – that focuses on approximately around 400 cities around the world analyzing data such as travel time, fuel costs and carbon emissions – analyzed over a year's traffic data on 5,000 kilometers (3,107 miles) of Istanbul's roadways. It was discovered that traveling a distance that usually takes only 15 minutes could take up to 50 minutes.

Apart from millions of its inhabitants who often commute from the Asian to the European part of Istanbul and vice versa for work, Istanbul is also one of the most visited metropolises in the world, packed with tourists year-round. The country's most famous city, and its largest by population, Istanbul remained the top draw for foreign visitors, welcoming more than 16 million tourists in 2022, according to official data from the Culture and Tourism Ministry in January 2023.

Particularly, during the morning rush hour of 8 a.m.-10 a.m. and the evening rush hour of 5 p.m.-8 p.m., traffic in Istanbul is usually congested. These are the usual and anticipated peak hours of traffic. However, unexpected traffic can arise at any time and in almost any area of the city.

Spikes in traffic are often witnessed prior to public holidays and during the start of school semesters. This raises questions about how traffic in the country's most populated city should be regulated, leading to proposals such as the system used in London – by levying a daily fare from vehicles entering the city center.

The increasing numbers of vehicles, traffic congestion and heavy maritime traffic are proven causes of pollution worldwide, and Istanbul is not an exception. The official figures from the Turkish Statistical Institute (TurkStat) reveal 4.94 million vehicles being registered in the megacity as of December 2022, corresponding to the combined population of 23 provinces in Türkiye. Transport experts in the past often reiterated that the number of vehicles in Istanbul "equals to one-fifth of the vehicles in all of Türkiye," thus directly posing a risk in terms of emissions.

Professor Mustafa Ilicali, who serves as the head of the Transportation Center at Istanbul Ticaret University, noted in October 2022 that several measures, including increasing the number of lanes, maritime traffic transport options and varied working hours, should be implemented to counter traffic congestion, and also the alarming pollution arising from it.

The "Dark Report" from the nonprofit Right to Clean Air Platform (THHP) shared on Thursday evaluated the air quality in the country. The report found that poor air quality in Türkiye, which had ranked sixth among the top 10 causes of death and disability for all ages, had moved up to fifth on the list of reasons that lead to air pollution-related diseases. The same report published in 2020 noted that Istanbul ranked high among the 45 provinces that surpassed national limits on pollutants, with Edirne and Denizli in the western part of the country making the list as well.

As per the last figures on air pollution compiled by Anadolu Agency (AA) in January, the average particulate matter (PM10) – an indicator of air pollution concentration measured in Istanbul in 2021 – stood at 38.2 micrograms per cubic meter. Yet, this figure was recorded at 41.5 micrograms per cubic meter in 2022, thus showing an increase of 9%.