"I'm hereby directing the Department of Defense and Pentagon to immediately begin the process necessary to establish a Space Force as the sixth branch of the armed forces," Trump said.

"We are going to have the Air Force, and we are going to have the Space Force, separate but equal," he added.

Details about the role and timing of any new space force were not immediately clear.

However, the creation of a new branch of the military cannot happen from one day to the next, as Congress would have to pass a law authorizing it first.

Trump has previously supported the idea of creating a sixth branch of the armed forces, adding to the US Army, Air Force, Marines, Navy and Coast Guard.

Debate over the issue has raged in Congress for years, with some supportive of the idea and others insisting space duties remain under the Air Force as they are now.

"When it comes to defending America it is not enough to merely have an American presence in space, we must have American dominance in space," Trump said at the start of the third meeting of the National Space Council, an advisory body led by Vice President Mike Pence.

Trump also signed a directive on space traffic management, aimed at boosting public-private monitoring of objects in orbit so as to avoid collisions and debris strikes.

A statement released by the White House said the move "seeks to reduce the growing threat of orbital debris to the common interest of all nations."