Oct 18 (Reuters) - European campaign group Transport & Environment (T&E) on Wednesday urged leasing firms to stop renting out fossil fuel vehicles by 2028 and said the top rental companies, with a combined fleet of 9.3 million, were lagging in the switch to electric.

Of Europe's top seven rental companies, which shape new car sales and the used car market, not one had committed to phasing out fossil fuel vehicles, the report "Stuck in the fossil age" said.

Only Societe Generale unit ALD Automotive and BNP Paribas unit Arval had set medium-term targets for purchasing electric vehicles (EVs). ALD, for instance, aims to have plug-in hybrids and fully-electric vehicles make up 50% of its sales by 2026.

By comparison, carmakers including Ford, Nissan and Stellantis have committed to selling only EVs by 2030.

The report said Arval and others, including Stellantis and Credit Agricole joint venture Leasys, plus Renault unit Mobilize Financial Services, lay claim to green credentials, such as switching to electric faster than the rest of the market.

But by examining car registration data T&E said that, with the exception of ALD, the leasing companies' claims are false.

"Our investigation clearly shows that all leasing companies... are making green leadership claims that are not backed up by evidence," the report says. "In other words, leasing companies are greenwashing."

Examining data from 11 EU countries for the first half of 2023, T&E found that in most of them leasing companies lag the rest of the market in buying fully-electric cars.

Across the EU as a whole, T&E found EVs made up just over 10% of leasing companies' car purchases, the same share as for the rest of the market.

"The steps towards real green leadership are clear," T&E said in its report. "What remains unclear is whether the major leasing companies will take these steps or remain rooted in the fossil age." (Reporting By Nick Carey; editing by Barbara Lewis)