President Trump will ask Congress for $1.5 billion this year to begin work on the wall he promised to build at the U.S.-Mexico border.

The money is part of a $30 billion supplemental spending request that’s being sent to lawmakers on Thursday, according to White House budget director Mick Mulvaney.

The request could trigger a fierce partisan showdown over the controversial wall proposal, as well as Trump’s broader efforts to crack down on illegal immigration.

ADVERTISEMENT

Trump is effectively making a down payment on one of his major campaign promises — the proposed border wall was a rallying cry of his presidential campaign, and he promised to make Mexico pay for it.

Senate Democrats have warned Republicans they could risk a government shutdown ahead of a funding deadline next month if they insert “poison pills,” such as money for the wall, into spending bills.

Mulvaney told reporters Wednesday the money would be used to begin developing technologies and locations for the wall.

The supplemental request also boosts funding for defense and other border security measures Trump has called for as part of a push to ramp up deportations of people living illegally in the U.S.

“I think the funding provides for a couple of pilot cases … different kinds of barriers in different kinds of places,” the budget director told reporters. “We try and find the most cost-efficient, the safest and also the most effective border protections."



Trump will also ask for $2.6 billion in funding for the wall in his fiscal year 2018 budget request, which is also being released Thursday.

That document is Trump’s “topline” budget for next year and doesn’t include projections over a decade. The full funding request for the wall could come as early as May, when the president releases his broader budget proposal.

But many obstacles stand in the way of completing the project, which could cost more than $20 billion, according to internal Trump-administration estimates

The U.S. government will have to initially foot the bill, because Mexico has resisted Trump’s demands. Trump officials have not said how they plan to compel Mexico to pay, but some directives have instructed agencies to take stock of foreign aid to the U.S.’s southern neighbor.

Democrats in the Senate say they will not move a government funding bill with funding for the wall included, which would almost certainly take 60 votes to clear the upper chamber.

"We believe it would be inappropriate to insist on the inclusion of such funding in a must-pass appropriations bill that is needed for the Republican majority in control of the Congress to avert a government shutdown so early in President Trump’s administration," Democratic leaders wrote in a letter this week.

Lawmakers have until April 28 to pass a measure to keep the government funded and avoid a shutdown.

Whether the wall funding triggers a shutdown fight is largely up to GOP leaders in Congress. If they package the supplemental spending request with the broader funding bill, Democrats could follow through on their threat to block the entire measure.

But if the supplemental bill is considered separately, that problem could be avoided.