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Story highlights

Congress rejected a request for more wall money earlier this year

The budget would also fund border technology and immigration enforcement hiring

(CNN) —  

President Donald Trump’s 2018 budget calls for more spending for border security and immigration enforcement – but the ask is still modest compared to what fulfilling his campaign pledges would likely cost.

The budget proposed by the White House on Tuesday includes $2.6 billion for border security – $1.6 billion of which will be for “bricks and mortar for a wall,” Office of Management and Budget Director Mick Mulvaney told reporters on Monday.

A source familiar with the budget justification says the money would largely cover just a few dozen miles of wall, tracking what the administration had previously proposed for the $1 billion it asked for unsuccessfully for 2017 construction.

As CNN previously reported, that $1 billion was requested for just 62 miles of border barrier, 14 of which was replacement fencing.

Estimates for funding a full wall across the entire Southern border have ranged in the tens of billions of dollars. Despite Trump’s repeated pledges to immediately begin on such a wall, his Department of Homeland Security has made clear that it would consider a variety of border barrier options and would not seek to build them “from sea to shining sea,” as Secretary John Kelly told Congress last month.

DHS received no additional money for new wall construction in 2017 but did get approval from Congress to use $20 million originally marked for other purposes to fund construction of prototypes for a future wall project.

In addition to the wall money, another $1 billion would cover investments at the border like aircraft, communications equipment, weapons, surveillance technology, road infrastructure and inspection equipment, according to budget documents provided by the White House.

The budget will make further requests for immigration enforcement, including $300 million to support recruiting, hiring and training for the vast increase in agents for Customs and Border Protection and Immigration and Customs Enforcement that Trump has called for.

Though the President has asked for 10,000 new immigration officers and 5,000 new Border Patrol agents, the 2018 budget would only support bringing on 500 new Border Patrol agents and 1,000 new ICE officers. CBP’s internal estimates obtained by CNN have shown that hiring a full 5,000 new agents could take decades.

The White House is also asking for $1.5 billion to support Trump’s efforts to substantially increase detentions and deportations of undocumented immigrants by funding detention and removal efforts.

It’s doubtful the budget has much momentum in Congress.

Lawmakers failed to pass any supplemental money in 2017 for the wall when it came up with a last-minute package to keep government funded past an April deadline. Democrats refused to agree to any money for the wall or what they call Trump’s “deportation force,” although some money for technology, hiring and detentions was approved.

In his briefing with reporters, the former lawmaker Mulvaney acknowledged that Congress generally prefers to write its own budgets over what the President sends over.

Still, he said, the budget reflects the administration’s priorities and the hope is that Congress will work to meet them.

“We take this very seriously. Why? There’s a certain message here,” Mulvaney said. “And the message is from the President to the Congress saying, ‘Here’s what my priorities are… ‘One of the big ticket items is I want more money for defense, I want more money for border security.’”