Germany's Green Party co-leader, Felix Banaszak, is taking an unconventional approach to campaigning ahead of three state elections next month, ferrying potential voters around Berlin in his very own "Banaszak Taxi."

Speaking ahead of his first drive on Wednesday, the Greens co-chief said the idea was a literal take on a political metaphor. "Politics should pick people up where they are and take them to their destination. I thought I'd take that literally," he said.

"I drive a car the way I do politics: free from fear and with great joy," Banaszak said.

Anyone who wants to be driven by the Greens co-leader and have a conversation with him can register their interest on a website. The 36-year-old said he'd already had many submissions.

"I think I'll also help people move a mattress and go shopping," he said. "But the opportunity is above all meant to be a chance to talk in the car about what is on people's minds."

Those tempted by a taxi ride don't need to worry about Banaszak's driving; he said he has so far avoided accidents and - largely - scratches.

Elections are due in September in the states of Saxony-Anhalt, Mecklenburg-Vorpommern and Berlin. In the two states outside the capital, the Greens are polling close to the 5% threshold required to enter the state parliament. In Berlin, they are polling between 15% and 19%.

In Saxony-Anhalt and Mecklenburg-Vorpommern, the stakes go beyond votes for the Greens, Banaszak said.

He said the question was also whether "the only force" that took environmental protection, nature conservation and climate change measures seriously would disappear from the state parliaments. It is also about whether "an anti-democratic, anti-constitutional, far-right, in parts fascist party" - a reference to the anti-immigrant Alternative for Germany (AfD) - would get the chance to govern a federal state, he said.

The AfD is set to see record gains in those elections. In Saxony-Anhalt, the party could even gain an unprecedented absolute majority, allowing it to enter a state government for the first time.