Elon Musk’s Tesla has warned that Donald Trump’s trade war could expose the electric carmaker to retaliatory tariffs that would also affect other automotive manufacturers in the US.

In an unsigned letter to Jamieson Greer, the US trade representative, Tesla said it “supports fair trade” but that the US administration should ensure it did not “inadvertently harm US companies”.

Tesla said in the letter: “As a US manufacturer and exporter, Tesla encourages the Office of the United States Trade Representative (USTR) to consider the downstream impacts of certain proposed actions taken to address unfair trade practices.”

The company, led by Musk, a close ally of Trump who is leading efforts to downsize the federal government, said it wanted to avoid a similar impact to previous trade disputes that resulted in increased tariffs on electric vehicles imported into countries targeted by the US.

Tesla said: “US exporters are inherently exposed to disproportionate impacts when other countries respond to US trade actions. The assessment undertaken by USTR of potential actions to rectify unfair trade should also take into account exports from the United States.

“For example, past trade actions by the United States have resulted in immediate reactions by the targeted countries, including increased tariffs on electric vehicles imported into those countries.”

Trump has imposed significant tariffs that will affect vehicles and parts made around the world.

The EU and Canada have announced large-scale retaliations for tariffs on steel and aluminium imports into the US, while the UK has so far held off on announcing any countermeasures.

Tesla’s share price has fallen by more than a third over the last month over concerns about a potential buyer backlash against Musk, who has shown support for Germany’s far-right Alternative für Deutschland party, theatrically brandished a chainsaw at a conservative conference, and accused Keir Starmer and other senior politicians of covering up a scandal over grooming gangs.

This week Trump said he was buying a “brand new Tesla” and blamed “radical left lunatics” for “illegally” boycotting the EV company – a day after Tesla’s worst share price fall in almost five years.

Tesla said: “As USTR continues to evaluate possible trade actions to rectify unfair trade practices, consideration should also be given to the timeline of implementation. US companies will benefit from a phased approach that enables them to prepare accordingly and ensure appropriate supply chain and compliance measures are taken.”

Separately on Friday, the German carmaker BMW reported that net profits slumped more than a third last year, as the owner of Mini and Rolls-Royce Motor Cars warned of the potential impact of US trade tariffs.

The company reported a 37% fall in net profits to €7.68bn (£6.4bn) in 2024, and expects an earnings margin for cars of 5% to 7% this year.

BMW reported a margin of 6.3% for last year, the lowest in four years, against a target of keeping carmaking returns above 8%.

“A challenging competitive environment, trade and geopolitical developments could all have a significant impact on business performance,” the company said.

BMW’s forecasts account for all tariffs imposed up to 12 March, including levies on steel and aluminium, a 20% tariff on China and 25% on Canada and Mexico.

The company continues to struggle in China, where local EV producers such as BYD have taken market share, and sales of BMWs and Minis fell 13.4% year on year. BMW’s overall car sales dropped 4% last year to 2.45m.

Last month, BMW paused a £600m investment into a Mini car assembly plant in Oxford amid declining demand for EVs.