A fuel injector for a turbine engine is provided. The fuel injector includes a body including an admissions chamber for admitting fuel under pressure, a stop valve mounted in the body downstream from the admission chamber and designed to open at a first determined fuel pressure and to remain open beyond that first pressure in order to feed a primary fuel circuit, and a metering valve mounted in the body downstream from the stop valve and designed to open above a second determined fuel pressure, greater than the first pressure, and to remain open above the second pressure in order to feed a secondary fuel circuit. The stop valve and the metering valve form a common movable assembly.