Union the KhPZ started series production of the T-34, the most-produced tank of World War II. Series production began in June 1940 in Kharkiv, and later in the Stalingrad Tractor Plant and Krasnoye Sormovo Shipbuilding Plant. In 1941, due to German advances, the factory and design shops were evacuated to the Ural mountains; the plant was merged with Uralvagonzavod in Nizhny Tagil into one enterprise called Ural Tank Plant No. 183. After Soviet victory over the Germans, it began production of the new T-44 tank in 1945, and the first prototypes of the T-54. After the war was over, the design bureau and factory gradually transferred all operations back to Kharkiv. The "No. 183" designation was left in Nizhny Tagil, while in Kharkiv the factory merged into Factory No. 75, a previously existing plant known for its T-34 diesel engines. T-54 production was started in the Urals and Kharkiv in 1947–48, and the move ended with the 1951 re-establishment of the Design Bureau, now called KB-60M, in Kharkiv. In 1957, the Factory No. 75 was renamed Malyshev Plant, and next year it took up production of T-55, the most-produced tank ever. The bureau also designed OT-54 and TO-55 flame-thrower tanks, for production at the Omsk Transport Machine Construction Plant. In 1967, T-64 tank production began here, as well as in the Kirov Plant and in the Uralvagonzavod. The T-80 tank, with a high performance gas turbine engine was produced beginning in 1983, followed in 1985 by a more conventional diesel model, T-80UD. Finished tanks were assembled in several plants, but Soviet industrial planning prevented any region from being able to establish independent arms production. Components and sub-assemblies were produced in different factories, the Malyshev Factory specializing in engines and transmissions. In independent Ukraine The Malyshev factory's million-square-metre facility produced 800 tanks in 1991, but underwent difficult times after the breakup of the Soviet Union, producing only 46 tanks until 1996, when a $650 M contract was signed to supply 320 T-80UD tanks to Pakistan. Fulfilling the contract was difficult — the distributed nature of Soviet military industry forced reliance on Russian factories for parts, and Russian political interference forced the development of local capabilities, resulting in the T-84 tank design. Like many Ukrainian industries, Malyshev was not allowed to negotiate contracts directly with foreign governments, but had to rely on Ukrspetsexport, a government arms-trading company. Although Malyshev was denied exporter