President Trump signed an executive order further solidifying U.S. policy toward mining and resource acquisition in space.

According to Space.com, the executive order has been in the works for roughly a year, and is “called Encouraging International Support for the Recovery and Use of Space Resources.” The order follows the 1967 Outer Space Treaty, not the 1979 Moon Treaty that was largely ignored by the U.S. and other space-capable nations. Under the 1967 Outer Space Treaty, mining and resource gathering in space is allowed.

“As America prepares to return humans to the moon and journey on to Mars, this executive order establishes U.S. policy toward the recovery and use of space resources, such as water and certain minerals, in order to encourage the commercial development of space,” said Scott Pace, deputy assistant to the president and executive secretary of the U.S. National Space Council.

With the U.S. once again making space exploration a priority, including a planned moon based within the decade, this executive order provides clear guidelines for U.S. space organizations.