China’s space program must help protect the country’s national security; however China is against a space arms, the government said in a policy paper issued on Tuesday.

President Xi Jinping has called for China to establish itself as a space power, and it has tested anti-satellite missiles, in addition to its civilian aims.

China has frequently said its space program is for peaceful purposes, but the U.S. Defense Department has highlighted its increasing capabilities.

“China always adheres to the principle of the use of outer space for peaceful purposes, and opposes the weaponisation of or an arms race in outer space,” the government said in its policy paper.

The program must also “meet the demands of economic, scientific and technological development, national security and social progress”, the paper added.

“Over the past 60 years of remarkable development since its space industry was established in 1956, China has made great achievements in this sphere, including the development of atomic and hydrogen bombs, missiles, man-made satellites, manned spaceflight and lunar probes,” it said.

China accomplished its longest manned space mission to date last month, when two astronauts spent 30 days aboard the Tiangong 2 space laboratory, or “Heavenly Palace 2”.