WASHINGTON (AP) — President Donald Trump wants to use the military to secure the U.S.-Mexico border until his "big, beautiful wall" is erected.

He said during a news conference Tuesday: "Until we can have a wall and proper security, we're going to be guarding our border with the military."

He has been frustrated by the lack of progress on fulfilling the signature promise of his campaign.

Federal law prohibits the use of active-duty service members for law enforcement inside the U.S., unless specifically authorized by Congress. But over the past 12 years, presidents have twice sent National Guard troops to the border to bolster security and assist with surveillance and other support.

The administration appears to be considering a model similar to a 2006 operation deployed by President George W. Bush