DW: Manipulated fuel efficiency and emissions data plus accusations of widespread collusion among Germany's major carmakers - are we witnessing the creeping demise of the country's flagship industry?

Ferdinand Dudenhöffer: It looks as if the German auto industry is in the process of tearing itself apart. For two years, there's been a host of negative headlines, almost on a weekly basis. Police raids on Porsche, Mercedes, Audi and VW; diesel car emissions which may soon prevent people from driving in downtown areas. Laws have been watered down; there's widespread manipulation. It's not exactly looking good.

The German auto industry will have to turn the corner very fast. The forthcoming diesel summit [among policymakers and executives] in Berlin may contribute to this. But only if it's a real summit, without the players only looking for car refitting schemes and software update solutions.

Rather, they need to look to the future as the UK and France have done which have announced dates for the exit of combustion engines, including diesel engines, because the latter cannot be saved anyway. Diesel is a burden on the industry, period.

In the foreseeable future, the sale of cars with combustion engines will be banned. What do you make of such rigid measures?

It's OK and alright that policymakers send out the right signals in time. We're talking about a 2040 exit in the case of France and the UK. That's more than 20 years to go; enough time to make a smooth transition and far better than acting in a hectic manner.

We simply have to find a way of leaving behind means of transportation that cause CO2 and move on to CO2-free mobility. We have to make our towns much better places to live in, and that's what we need electric cars for. That's why it's good to tell people today when the exit will come instead of pretending that diesel technology will be around forever and a day.

The German chancellor's objective to have 1 million e-cars in use on German roads by 2020 is obviously unrealistic. So what should happen at the forthcoming Berlin summit?

First of all, it should be an honest summit. But it's more likely to be a repair works summit, with those attending trying to cheat their way through. And with carmakers trying to avoid diesel car bans in cities by tweaking their software a bit - at no additional cost.

The chancellor is hoping for a quiet general election [on September 24], and that's mainly why this summit has been called. It's bound to be a backward-looking event.

A forward-looking summit would be one at which you announce the date for a diesel exit and tell people to cut diesel subsidies and tax diesel cars exactly as you would tax petrol-powered vehicles. You could then use the extra revenue to expand the network of charging stations for e-cars. And you would have to tell industry when exactly only e-cars would be allowed in terms of new registrations like in Norway, France and the UK.

But would it not also be high time to start thinking about different mobility concepts, such as better intertwining the various modes of transport?

It's already being done. Networking is already in place, at least to some extent. But look: that story about getting more goods to be transported away from the roads and onto the rails has been told for 50 years. But telling such stories for ages doesn't get us anywhere.

Besides using more e-cars, we're also approaching the age of autonomous or at least semi-autonomous driving. In this area, connectivity is easy to bring about. Owning a car will no longer play such a decisive role. We're talking about calling cabs or other vehicles that come to your place when you need them, and which will cost a lot less.

Rail and bus operators will also have to invest a bit more in the future. When you need to change trains you're constantly afraid you will fail because doors don't open or what have you. Trains are late if it's raining and tracks are underwashed. So, trains have to become more reliable, and then we can do the trick!

Ferdinand Dudenhöffer is the director of the Center for Automotive Research at Duisburg-Essen University.