The present invention relates to a method of producing a cemented carbide body comprising providing: (1) a grain refiner compound comprising a grain refiner and carbon and/or nitrogen, and, (2) a grain growth promoter, on at least one portion of the surface of a compact of a WC-based starting material comprising one or more hard-phase components and a binder, and then sintering the compact. the invention also relates to a cemented carbide body comprising a WC-based hard phase and a binder phase, wherein at least one part of an intermediate surface zone has a lower average binder content than a part further into the body, and at least one part of an upper surface zone has in average a larger average WC grain size than the intermediate surface zone. The cemented carbide body can be used as a cutting tool insert for metal machining, an insert for a mining tool, or a coldforming tool.