The Supermarine Type 553 was a British prototype Mach 2 fighter that was never produced, only blueprints were made of the aircraft in 1953.
Supermarine Type 553 Wikipedia
The complexity of mach 2 flight was realised during the 545 development. Vickers-Supermarine proposed the 553 with a swept wing that would make the plane more aerodynamic than a straight wing design. It would be produced of aluminium alloy. The decision was close to make the aircraft because it would have to be made from heavier steel.
The 553 was not taken up; the Bristol 188 was accepted and a contract placed, however this aircraft was a failure also.