Boeing is facing new pressure after a whistleblower reported safety concerns over the manufacturing of some of its planes to US regulators.

Engineer Sam Salehpour accused Boeing of taking shortcuts in the construction of its 787 and 777 jets.

He claimed he was “threatened with termination” after raising concerns with bosses.

The whistleblower complaint, which was first reported by the New York Times, is the latest incident to focus attention on the safety of planes made by US-based Boeing, one of the world’s two major producers of commercial planes.

The company was already facing criminal investigation and other legal troubles, after an unused exit door broke off of one of its smaller 737 Max 9 planes shortly after take-off in January.