How the Royal Navy entered war with global fuel reserves

Could the Royal Navy fuel itself without American oil?

Yes. Britain had accumulated large global fuel reserves, although American supplies remained valuable as wartime consumption expanded.

The Royal Navy had built very large fuel stocks before the war. Former coaling stations at Ceylon, Australia, Singapore, and other imperial bases had been adapted to sustain an oil-fired fleet. American fuel therefore augmented an existing worldwide reserve system rather than creating it. The exchange shows the long lead time and geographic depth required for naval endurance.