The Russian deputy PM in charge of the defense industry, Dmitry Rogozin, has warned US President Donald Trump against taking the arms race into space, hinting at unpredictable negative consequences of such a plan.

“If this statement means placing weapons in space, the USA is opening Pandora’s box,” Rogozin wrote on Facebook after reposting a news report about Trump’s announcement that the United States might develop a new branch of military forces – the Space Force – in the near future.

Speaking to servicemen of the US Marine Corps at Miramar Air Station near San Diego, the US president admitted that he previously had not treated the idea of a separate Space Force with great seriousness, but said the plan now looks more feasible.

Russia had a separate Space Force between 2001 and 2011. In 2011, it was reformed into the Air and Space Defense Troops and, in mid-2015, merged with the Air Force. It has since been officially named the Air and Space Force of the Russian Federation.