Donald Trump and his administration seem to be inching closer to funding a border wall by bypassing Congress and redirecting federal money, including disaster relief funding meant for California and Puerto Rico.

According to Politico, the White House is “firming up plans” for executive action that would make use of this disaster relief funding for the wall.

The plan would also reportedly take money from Northern California flood control projects, as well as military construction money from the Department of Defense.

Disaster relief funding intended for Texas was at one point under consideration for redirection, too, reports CNN. But Politico doesn’t mention Texas as having its disaster relief funding at risk anymore, noting that the state’s Republican Sens. Ted Cruz and John Cornyn had pushed back on this.

Texas Gov. Greg Abbott also signed a letter saying he is “strongly opposed” to Texas’ Hurricane Harvey relief funding being used for the wall, per The Hill.

Redirecting federal money for the wall is a thorny situation in the first place and will surely be challenged in court.

As Politico explains: “By diverting disaster money intended for heavily Democratic California and Puerto Rico — instead of staunchly Republican Texas, which is still rebuilding after Hurricane Harvey — Trump opens himself up to criticism that he’s favoring red states over blue ones.”

A national emergency declaration, however, does not unlock unlimited powers and would be subject to court challenges. The White House counsel’s office has been studying two statues in detail that Trump could invoke under national emergency circumstances — and both come with problems.

One, 10 USC Section 2808, authorizes military construction projects that support the use of the armed forces. Those are typically things like barracks, helipads and other military fortifications. The other, 33 USC Section 2293, allows the Secretary of the Army to redirect funds from the Army’s civil works program for projects including “authorized civil works.” White House lawyers, however, expect to be challenged about whether the wall truly supports the armed forces or is an authorized civil work.