(Reuters) - The European Union should reject European automakers' push to weaken 2025 CO2 car emission targets and related fines, two European electric transport groups wrote in a letter to European Commission President Ursula von der Leyen on Friday.

The letter, seen by Reuters, said the EU executive, which will present auto sector plans on March 5, should not accept slower phasing in of emission targets or basing fines on a multi-year average and that any fines should go to subsidise the bloc's transition to electric vehicles (EVs).

EU carmakers, which are struggling to compete with Chinese rivals and bracing for U.S. tariffs, are urging the Commission to grant relief from fines they say could rise to 15 billion euros ($15.7 billion) if their fleets do not meet CO2 emission limits in 2025.

Any flexibility that pushes back the 2025 CO2 limits will only put Europe further behind China in EVs and have a chilling effect on EU investment plans in charging infrastructure, battery development and manufacturing, the letter from E-Mobility Europe and ChargeUp Europe said.

E-Mobility Europe represents EV makers, supply chain companies, fleet owners and infrastructure providers, while ChargeUp Europe focuses on the EV charging industry. Tesla is a member of both.

EU automakers say the problem they face is a shortage of demand, due in part to consumer concerns about inadequate charging infrastructure.

Aurelien de Meaux, chief executive of charging company Electra, said this was a false narrative and that EU charging stations could accept five to seven times more vehicles without being saturated and that his sector was investing billions of euros in infrastructure expansion.

"It would be a disaster to backpedal on policy," he said.

The groups said in the letter that the 2025 CO2 targets are achievable, pointing to 11 new models priced under 25,000 being launched and January 2025 EV sales up 40% year-on-year.

De Meaux also said the 15 billion euro fine figure was based on sales in the first six months of 2024 and so wrong. He said projections pointed to fines of perhaps 4-6 billion euros, which could be halved through trading credits with other companies.

The groups support targets or incentives for corporate fleets to electrify, given they make up about 60% of new car sales.

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