President Donald Trump announced Thursday the official establishment of the US military’s Space Command, CNN reported.

“Those who wish to harm the United States, to seek to challenge us on the ultimate high ground of space, it’s going to be a whole different ballgame,” Trump said at a White House ceremony marking the command’s establishment.

Space Command will become the 11th combatant command, joining the ranks of US Central Command.

“We no longer have the luxury of treating space superiority as a given,” Air Force Gen. John Raymond, the incoming US Space Command commander, told reporters at the Pentagon on Thursday.

Trump also spoke Thursday about the creation of a US Space Force, a military branch his administration wants to see established under the Department of the Air Force.

Space Command “will soon be followed—very importantly—by the establishment of the United States Space Force as the sixth branch of the United States Armed Forces,” Trump said, adding that the Space Force will “organize, train and equip warriors to support Space Command’s mission.”