The US navy secretary has warned that the “fragile” American supply chain for military warships means the Pentagon is at risk of having to rely on adversaries such as Russia and China for critical components.

Richard Spencer, the US navy’s top civilian, told the Financial Times he had ordered a review this year that found many contractors were reliant on single suppliers for certain high-tech and high-precision parts, increasing the likelihood they would have to be procured from geostrategic rivals.

Mr Spencer said the US was engaged in “great power competition” with other global rivals and that several of them — “primarily Russia and China” — were “all of a sudden in your supply chain, [which is] not to the best interests of what you’re doing” through military procurement.