MOSCOW (Sputnik) — According to Alexander Stadnik, Russia's trade representative to the United States, the rocket engines were initially sanctioned by the United States, but Washington removed them from the list.

"They must have understood that they needed this Russian equipment for development of rocket equipment, otherwise they would have to limit themselves in a series of expensive projects. It is evident that this is the reason the supplies of our engines were continued."

Stadnik noted that the sides were continuing cooperation with previously signed contracts.

In January, Russian rocket producer Energia signed a $1 billion contract with US Orbital Sciences Corporation for the delivery of 60 RD-181 engines. The contract also includes a provision on a range of services including flight training, installation of the engine and engine testing.

In the late 1990s, the Russian Energomash company won a contract with United Launch Alliance to supply RD-180 engines for the Atlas rockets. This contract, valued at about $1 billion, remains in place.

The West, led by Washington, has been imposing sanctions on Russia since 2014, when a military and political crisis in Ukraine escalated, with the US and the EU alleging Russia's involvement.