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.