He also suggested that The Pentagon pay for the estimated US$25 billion wall.
Trump threw Washington into a tizzy on Friday when he threatened to veto the omnibus spending bill, in part because it didn't include the $25 billion USA he'd tried to secure for the wall in a last-minute bargaining spree.
Only $641 million is earmarked for new primary fencing in areas that now have no barriers, and the money can be spent only on "operationally effective designs" that were already deployed as of last May.
The Washington Post's Philip Rucker, Ashley Parker and David Nakamura explain why President Trump still pledges to build a wall on the USA southern border.
Over the weekend, he tweeted, "Building a great Border Wall, with drugs (poison) and enemy combatants pouring into our Country, is all about National Defense".
President Donald Trump's had a startling new thought about his infamous wall.
Senior officials in Congress told The Post such a move was unlikely, and a senior official at the Pentagon said redirecting money from the 2018 budget would have to be done by lawmakers.
To find the money in the 2019 defense budget, Trump would have to submit a budget amendment that would still require 60 votes in the Senate, the official said.
The White House wouldn't comment today on a report that President Trump wants to siphon appropriations from the Defense Department, which took home about $700 billion in the omnibus spending bill, to fund his border wall project.
Mattis has sought to distance himself from contentious issues, chief among them the border wall, that have wounded USA relations with its southern neighbor.
Gallego's amendment to the National Defense Authorization Act (NDAA) previous year was seen as largely symbolic since there had been no proposal to use Pentagon funding for the wall.
"We have shared security concerns".
In a statement, his firm said the president and his team recently reached out to Webb and Washington, D.C. -based partner Tom Buchanan. "I'm going down to build the trust and show the respect on their Independence Day", Mattis said at the time.