The owner of Vauxhall has warned it is facing a €1.5bn (£1.3bn) bill for US tariffs just days after the European Union struck a trade deal with Donald Trump.

Stellantis said on Tuesday it had already incurred tariff-related costs of €300m for April to June, although it warned these would rise by a further €1.2bn for the final six months of this year.

The prediction assumes there is no change to tariffs currently being levied on cars shipped from Europe to the US, which have been in place since April.

It reflects the uncertainty still surrounding Sunday’s US-EU deal, and the staggering costs European companies face if the agreement is not finalised in the coming weeks and months.

Stellantis reported a 23pc drop in shipments to North America in the first half of 2025 alone, prompting a 4.6pc fall in the company’s share price in early trading.

The tariffs have made European cars more expensive for consumers while denting profitability for manufacturers.

The deal struck by Brussels and President Trump would cut the levies from 27.5pc to 15pc. That is up from 2.5pc before President Trump first launched his trade dispute, but still a significant reduction on current levels.

However, Ursula von der Leyen, the European Commission president, is facing a backlash from member states over the deal – which France and other critics have claimed is a humiliation for the Continent.

François Bayrou, the French prime minister, said the agreement marked a “dark day” for the “free peoples” of Europe, while Hungarian PM Viktor Orban complained Ms von der Leyen had been “eaten for breakfast” by Mr Trump.

Even Germany, which reluctantly supported the agreement, said it would still suffer “significant damage” under the pact.

It suggests that winning approval for the deal from member states will be a tricky process in the coming weeks.

Another point of anger for European leaders is the improved terms secured by Britain, which negotiated a 10pc tariff with the president. That is also up from 2.5pc before the dispute.

On Tuesday, Stellantis said it remained “highly engaged with relevant policymakers, while continuing long-term scenario planning”.

Exactly how much Stellantis itself would benefit from any deal remains uncertain.

Analysts at Morningstar on Monday suggested the company shipped fewer cars from Europe to the US than rivals, choosing instead to assemble more cars in Mexico and Canada.

As a result, Stellantis was likely to see no “meaningful upside”. Instead, they argued Porsche, Mercedes, BMW and Volkswagen – in that order – would be “the most significant beneficiaries of this trade deal”.

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