In a much-anticipated move, President Donald Trump on Wednesday signed a directive ordering federal funds to be diverted to begin building a massive wall along the U.S.-Mexico border.

While Trump long promised during the presidential campaign to build a wall, he insisted Mexico would pay for it, and the decision to use taxpayer funds and later seek reimbursement from Mexico is a hugely contentious move.

During a visit to the Department of Homeland Security, Trump signed two immigration-themed executive orders on Wednesday. One covers starting his promised border wall project, as well as expanding resources for DHS and Immigration and Customs Enforcement. The second seeks to strip federal funding for “sanctuary cities.”

Trump told DHS employees after a town hall meeting that one of his orders directs the “immediate construction of a border wall,” which he said is “so badly needed.”

“We are going to restore law and order,” Trump said, then immediately recognized U.S. Border Patrol and Immigration and Customs Enforcement officers in the room. The line is consistent with his self-designation as the “law-and-order” candidate in the 2016 presidential race.