US Senator John McCain stated that presence of the Russian citizens during the US National Security Space launches with the Russian RD-180 rocket engine raises new troubling questions and is another reason for ending US dependence on Russian rocket engines as quickly as possible.

US Senator John McCain expressed concern on Thursday over the necessary presence of the Russian citizens during the US National Security Space launches with the Russian RD-180 rocket engine, the Defense News reported Thursday, citing McCain's letter to US Secretary of the Air Force Deborah Lee James.

"This access and presence of Russian nationals to the launch vehicles of our most sensitive national security satellites raises new troubling questions and is yet another reason for ending our dependence on Russian rocket engines as quickly as possible," the letter read.

McCain also wondered why James "found it acceptable to have Russian nationals working for Roscosmos, a Russian state corporation, present at our most sensitive satellite launches."

In 2014, US Congress passed a law demanding the United States phase out its reliance on the Russian-made RD-180 rocket engines.

However, in the two years after implementing a purchasing ban on the RD-180 engines, Congress has been forced to lift that ban to ensure the United States access to space.

Russia's RD-180 engines are used for the Atlas V rocket space launches.

Source: Sputnik News