A citizens’ initiative calling for a ban on private car use in central Berlin would create the largest car-free urban area in the world.

The campaign group Berlin Autofrei has taken the first step in a process known as the people’s referendum, submitting a petition with more than 50,000 signatures calling for a ban covering the 88 sq km (34 sq mile) area circled by the “S-Bahn ring” trainline – an area roughly equal in size to all the boroughs in London’s zones 1 and 2.

People who depend on their cars for their trade or because they have impaired mobility would be exempt, as would emergency services. Everyone else would each be permitted up to 12 rented car journeys a year – in case they need to move house, for example.

But is banning cars necessary, and what is wrong with electric vehicles? “We would need about half of cars to go electric next year in order to meet the federal government’s own targets for transportation emissions,” said Nik Kaestner, from the campaign. “That clearly isn’t going to happen – currently only 1.3% of vehicles in Germany are electric. So the only solution is to reduce the amount of driving that’s happening, not just to change how we drive.”

Manuel Wiemann, a spokesperson for the initiative, said cars also polluted through tyre wear, “occupy far too much common space and unnecessarily endanger human lives, whether electric or diesel”.

A 2014 report commissioned by Berlin’s regional parliament found that 58% of traffic space was devoted to cars, even though only a third of journeys on Berlin streets (and only 17% within the S-Bahn ring) were made by car. Only 3% was set aside for bicycles, which accounted for 15% of journeys (18% within the ring).

Parked cars took up 17 sq km. In total, almost 20 times more space was dedicated to cars than to bicycles in one of Europe’s most renowned cycle-friendly cities. Three-quarters of road deaths are pedestrians or cyclists.

Nina Noble, one of the initiative’s founders, said: “It’s as much about our immediate environment as it is about the environment at large. It’s about how we all want to live, breathe and play together. We want people to be able to sleep with their windows open, and children to be able to play in the street again. And grandparents should be able to ride their bicycles safely and have plenty of benches to take a breather on.”

Although historically anti-car campaigns in Europe have tended to have very limited success, Berlin Autofrei may prove different. The campaign is using a special form of direct democracy enshrined in the German constitution. Another people’s referendum led to the recent landmark vote to expropriate thousands of houses from Berlin’s biggest landlords.

In the first stage of a three-part process, a group must collect the signatures of 20,000 citizens in favour of a proposed law change in a given timeframe. In the second stage, 170,000 signatures must be collected. If the government refuses to implement the law after these two stages, the question is put to a public vote.

Having collected 50,333 signatures in the first stage, the campaigners are feeling confident.

“The federal environmental ministry did a study recently and 91% of people said they would be happier without a car. Moreover, only a third of individual Berliners actually have a car,” said Kaestner.

But he admitted this “doesn’t mean people will automatically be in favour. If it does get to a final vote, it will be about motivating the base just like in every other tight election.”

A previous referendum initiative calling for a cycle-friendly mobility law never had to go to a public vote, because the government adopted the proposed law after stage two of the process. There is a possibility that it may do the same with Autofrei, as the Greens will play a significant role in the next governing coalition after their vote share increased to 18.9% in Berlin in September’s elections.

For the moment Berlin Autofrei still has a long way to go. But if there was ever a chance for a radical transformation of road space, then when if not now? “And where,” said Wiemann, “if not in Berlin?”