The White House has asked the U.S. Army Corps of Engineers to look into projects approved in a bill providing disaster relief for Puerto Rico, Texas, California and Florida to see where funding could be diverted to build a wall along the border with Mexico, according to a congressional aide familiar the discussions.

Almost three weeks into a partial government shutdown, President Donald Trump has signaled he may seek a way out of the impasse over funding a wall by declaring a national emergency at the border with Mexico. Federal law allows the president to halt military construction projects and divert those funds for an emergency.

On Thursday, White House officials asked the U.S. Army Corps of Engineers to comb a spending bill passed last year that provided disaster relief for Puerto Rico, Texas, California and Florida to see which projects could be delayed and the funds diverted to the wall. Those projects, which have been approved for construction but for which funding hasn’t yet been obligated, include flood-control efforts to prevent damage from future natural disasters in states recently hurt by them.

“This money is supposed to be used on projects to defend Americans from natural disasters and rebuild communities impacted by them,” Rep. Anthony Brown, D-Md., tweeted on Thursday. “We’ll have fewer resources to protect places like Puerto Rico and Houston, TX from being destroyed.”

An expanded version of this report appears on WSJ.com.

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