By the 1960s, the United States military was developing the swing-wing F-111 project as a follow-on to the Republic F-105 Thunderchief, a fast low-level fighter-bomber designed in the 1950s with an internal bay for a nuclear weapon. There had been some interest in the TSR-2 from Australia for the Royal Australian Air Force (RAAF), but in 1963, the RAAF chose to buy the F-111 instead, having been offered a better price and delivery schedule by the American manufacturer. Nonetheless, the RAAF had to wait 10 years before the F-111 was ready to enter service, by which time the anticipated programme cost had tripled. The RAF was also asked to consider the F-111 as an alternative cost-saving measure. In response to suggestions of cancellation, BAC employees held a protest march, and the new Labour government, which had come to power in 1964, issued strong denials.