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Story highlights

Estimates for President Donald Trump's wall have ranged in the tens of billions

But the supplemental only sets aside $1 billion for the wall

(CNN) —  

The Trump administration is planning to ask for a relatively small amount of money to start building the President’s long-promised border wall this year – far short of estimates of what the wall might cost, according to preliminary numbers shared with CNN.

Despite President Donald Trump’s repeated calls to begin immediately building a substantive wall along the entire Southern border, which experts say would cost tens of billions of dollars, the administration is not asking for even a fraction of that in the near-term.

Congress is preparing to receive a request from the administration on March 16 for supplemental funds for fiscal year 2017, according to two sources familiar with the timing, along with an overall budget request for fiscal year 2018. Office of Management and Budget Director Mick Mulvaney previously said the supplemental request, which will also include defense spending, will total $30 billion.

But according to preliminary numbers shared with CNN by a source familiar with the proposal, only $6.6 billion of the supplemental budget request will go toward border security – and just $1 billion of that will be for the wall.

The source referred to the money as a “down payment” of sorts, with more to be allocated later.

Estimates for Trump’s wall have ranged in the tens of billions. Senate Majority Leader Mitch McConnell estimated the wall would cost up to $15 billion, and an internal estimate considered by Department of Homeland Security and viewed by CNN reached $21.6 billion.

But the supplemental only sets aside $1 billion for the wall and another $1.8 billion to support other aspects of the President’s executive orders on border security and immigration. That money will go toward detention costs, including increasing the number of beds and hiring more immigration and border agents.

The remaining $3.8 billion in the supplemental request would go to other DHS expenses, including $1.7 billion to Immigration and Customs Enforcement for enforcement, investigations, and training; $1.4 billion to the Coast Guard; and $451 million for Customs and Border Protection operations.

Separately, two sources familiar with the administration’s FY2018 budget request told CNN the plan is to boost DHS’s total budget by 6%, up to $43.8 billion. That would be paid for with cuts to the Coast Guard, TSA and FEMA, as first reported by Politico.

Of that increase, $2.9 billion was for CBP, $2.1 billion for ICE, $1.4 billion for the border wall, $555 million for fence replacement along the border, $915 million for surveillance technology backing up the border barrier, a $1.9 billion increase to pay for detention space and transportation costs and then $100 million for the first 10% of the 5,000 CBP border agents that Trump has called for hiring in his executive order and $185 million for the first 10% of 10,000 new ICE officers also called for.

An Office of Management and Budget spokesman said any numbers were “premature.”

“The budget blueprint will be released in mid-March. It would be premature for us to comment – or anyone to report – on the specifics of this internal discussion before its publication,” John Czwartacki said. “The President and his Cabinet are working collaboratively as we speak to create a budget that keeps the President’s promises.”

Lawmakers on the Hill have been expecting the supplemental debate to be the first real consideration of Trump’s immigration policies in Congress.

Several lawmakers on both sides of the aisle anticipate that it could get attached to a provision protecting recipients of Deferred Action for Childhood Arrivals – former President Barack Obama’s policy granting some protections from deportation and work authorization to undocumented immigrants who were brought to the US as children and are otherwise clear of criminal records.

In order to pass the Senate, the supplemental will need eight Democrats to support the bill in addition to all 52 Republicans. And Democratic support could be needed in the House if budget hawk conservatives don’t believe the supplemental funds are adequately paid for.

The White House and GOP leadership have not yet signaled any willingness to compromise on a bill protecting DACA recipients, though both have spoken sympathetically of that group of undocumented immigrants and said they are not a priority for deportation.

CNN’s Ryan Browne contributed to this report.