BERLIN — A German car lobby association allegedly used its close ties to the country's transport minister, Volker Wissing, to provide industry and lobbyists with access in return for payment, according to an investigation by a German public broadcaster.

The association, Mobil in Deutschland, offered VIP meetings with the transport minister and his state secretary, Oliver Luksic, in connection with a campaign to promote a biofuel called HVO100, according to an investigative report by public broadcaster ZDF. The campaign itself was financed, in part, by lobby groups representing car service stations and dealerships, as well as an energy supplier.

Industry and lobbyists could pay €9,900 to receive a "premium partnership" that included the opportunity to meet the minister. Luksic acted as the campaign's honorary patron and shot a promotional video for HVO100, which has been available at German gas stations since May.

Luksic suspended his patronage in reaction to the report, the transport ministry said in a statement, adding it "resolutely rejects any accusations of undue influence by interest groups and of arranging appointments with the house management in return for payment."

Michael Haberland, Mobil in Deutschland's president, told ZDF in a statement that the "premium partnership" option had only been sent out a dozen times in early 2024, and is no longer offered in the same form.

Wissing and Luksic, who are politicians in Germany's pro-business Free Democratic Party (FDP), came under intense criticism after the report aired.

"It is not the job of politicians to allow themselves to be used for misleading lobby campaigns,” said Christina Deckwirth from the transparency watchdog Lobbycontrol. "The aim behind this is to overturn the decision taken in Brussels to phase out combustion engines."

Germany dropped its last-minute opposition to the EU's de-facto ban on the sale of new combustion engine cars from 2035 by striking a deal that will allow the continued sale of cars running exclusively on synthetic e-fuels.

HVO, or hydrotreated vegetable oil, is not an e-fuel, but is made from oils and fats from vegetable and animal sources. Still, some view HVO as paving the way for e-fuels.

"HVO is practically the pioneer for synthetic fuels, for e-fuels, and this must be a successful story," Haberland, the car association president who was in charge of the HVO100 campaign, told ZDF in an interview. He lauded Wissing and Luksic for having "really pushed this issue forward."

Conservative parties in Germany are increasingly pushing to overturn the 2035 ban on the sale of new combustion engine cars — a central pillar of the EU's Green Deal plan to cut planet-warming emissions. The center-right Christian Democratic Union (CDU) and the liberal FDP argue that openness to new technologies, instead of bans, are needed on the path to climate neutrality.

"The approval [of HVO] is an important step towards more climate protection in transportation," the German transport ministry wrote regarding HVO on its website.

Environmental organizations, on the other hand, have called the alternative fuel a sham solution whose backers wish to hinder the phase-out of fossil fuels.