As a result, secret weapon projects—including numerous nuclear weapons—were given lighthearted names such as Green Cheese, Blue Slug or Red Duster.

The Ministry of Supply was responsible for building and running the Royal Ordnance Factories, which produced explosives and propellants, filled ammunition, and constructed guns and rifles.

W. A. Robotham of Rolls-Royce was appointed chief engineer of tank design in the ministry in November 1941.

[5] Tanks were designed and built by private arms, engineering, and manufacturing companies, e.g. the Birmingham Railway Carriage and Wagon Company, English Electric in their Stafford Works, Leyland Motors, Nuffield Mechanizations, Vauxhall Motors, and Vickers-Armstrongs.

[6] The Ministry of Supply also arranged for the construction of a large number of "agency factories", which were run on its behalf by private companies, such as Nobel Industries.

From the beginning of the Second World War, the army research establishments were put under the control of the Ministry of Supply.

Examples include: Moreover, the Dutch Defence Chemical Laboratory escaped the German occupation of the Netherlands.

[8] Lord Portal was appointed as Controller of Production (Atomic Energy); and in 1950 the High Explosive Research Establishment at Fort Halstead was renamed the Atomic Weapons Research Establishment (AWRE), with William Penney as its first director.

The procurement powers of the Admiralty were largely unaffected, though their aircraft would now be supplied via the Ministry of Aviation.