A group of lawmakers warned Trump administration officials that they can’t build a 250-foot triumphal arch in Washington, D.C., without congressional approval — and that if they do move forward with the project, they could face consequences. In a letter sent Monday to Interior Secretary Doug Burgum and two National Park Service officials, six lawmakers cautioned that building President Donald Trump’s proposed arch in the nation’s capital would violate multiple statutes and that the NPS has “no power” to build it. The letter says the administration would be violating the Commemorative Works Act, which governs commemorative works in and around the nation’s capital.”

​“Since 1986, every memorial placed on federal land in the capital under the Act, more than forty in all, has come to Congress first,” reads the letter, signed by Sens. Angus King (I-ME), Jeff Merkley (D-OR), and Martin Heinrich (D-NM), and Reps. Jared Huffman (D-CA), Maxine Dexter (D-OR), and Yassamin Ansari (D-AZ). “The World War II Memorial alone required two acts of Congress before the NPS issued a construction permit. The Arch’s sponsor has sought no act at all.”

​The letter said the proposed arch also violates a 1912 statute, which states that a building or structure can’t be erected on any federal grounds in Washington “without express authority of Congress.”