The introduction of the first jet engines in the late-World War II period led to calls for new jet-powered versions of practically every aircraft then flying. Among these was the design of a replacement for the de Havilland Mosquito, at that time among the world's leading medium bombers. The Mosquito had been designed with the express intent of reducing the weight of the aircraft in order to improve its speed as much as possible. This process led to the removal of all defensive armament, improving performance to the point where it was unnecessary anyway. This high-speed approach was extremely successful, and a jet-powered version would be even more difficult to intercept.