Elon Musk, the company’s chief executive, is fast losing out to Chinese electric carmakers in Tesla’s second-most-important market.

This suggests that a reaction from consumers who dislike Mr Musk’s antics are only one reason for falling sales. An updated Model Y, Tesla’s best-selling vehicle, has just gone on sale. In preparation Tesla ran down inventory of the old model, crimping supply. Customers doubtless held off purchases until the new car was available.

Tesla's reported letter comes after unpredictable Trump trade policy moves that have unsettled businesses and markets.