In order to increase range, studies were made of a significantly larger Mirage IVB design, powered by two Snecma license-built Pratt & Whitney J75 engines and having a wing area of 120 m² (1,290 sq ft) compared to 70 m² (750 sq ft) of the prototype IV, as well as a speed of Mach 2.4 and a gross weight of . The "Mirage IVB" proposal had been instigated as a response to interest by de Gaulle in ensuring that two-way (including the aircraft's return to France) strike missions could be flown. However, development of the aircraft was ultimately cancelled in July 1959 due to the greater cost involved, a decision having been taken to rely upon aerial refueling instead also being a factor.