Russia

The Tupolev Tu-144 was the first supersonic passenger jet.

In Russia but I think there is a Tupolev plant in the Ukraine,when the Soviet Union broke up a lot of military manufacturing plants went with their respective countries.

The Tupolev Tu-144 (NATO reporting name: Charger) was the first supersonic transport aircraft (SST), constructed under the direction of the Soviet Tupolev design bureau headed by Alexei Tupolev. Some western observers nicknamed the plane Concordski (sometimes Konkordski), as the Tu-144 was very similar to Concorde. A prototype first flew on 31 December 1968 near Moscow, two months before Concorde. The Tu-144 first broke the sound barrier on 5 June 1969, and on 15 July 1969 it became the first commercial transport to exceed Mach 2, and the fastest commercial airliner ever.