US President Donald Trump speaks on trade tariffs in the Cabinet Room of the White House in Washington, DC on January 24, 2019. - Trump also spoke about the unfair trade practices at play in the world. (Photo by MANDEL NGAN / AFP)        (Photo credit should read MANDEL NGAN/AFP/Getty Images)
PHOTO: MANDEL NGAN/AFP/AFP/Getty Images
US President Donald Trump speaks on trade tariffs in the Cabinet Room of the White House in Washington, DC on January 24, 2019. - Trump also spoke about the unfair trade practices at play in the world. (Photo by MANDEL NGAN / AFP) (Photo credit should read MANDEL NGAN/AFP/Getty Images)
Now playing
01:09
Trump offers cryptic warning about his next move
Connolly
PHOTO: CNN
Connolly
Now playing
03:51
'I will not be lectured' on bipartisanship: Lawmaker fires back at Jim Jordan
US President Donald Trump speaks to the press from the South Lawn of the White House after announcing and initial deal with China in Washington, DC, prior to departing to Lake Charles, Louisiana to hold a campaign rally on October 11, 2019.
PHOTO: NICHOLAS KAMM/AFP/Getty Images
US President Donald Trump speaks to the press from the South Lawn of the White House after announcing and initial deal with China in Washington, DC, prior to departing to Lake Charles, Louisiana to hold a campaign rally on October 11, 2019.
Now playing
02:28
Romney says he's 'pretty sure' Trump will win 2024 nomination if he runs
Now playing
02:04
Senate moderates create obstacle for Biden's nominee
This picture taken 26 December 2011 shows the Pentagon building in Washington, DC.  The Pentagon, which is the headquarters of the United States Department of Defense (DOD), is the world
PHOTO: Staff/AFP/Getty Images
This picture taken 26 December 2011 shows the Pentagon building in Washington, DC. The Pentagon, which is the headquarters of the United States Department of Defense (DOD), is the world's largest office building by floor area, with about 6,500,000 sq ft (600,000 m2), of which 3,700,000 sq ft (340,000 m2) are used as offices. Approximately 23,000 military and civilian employees and about 3,000 non-defense support personnel work in the Pentagon. (Photo credit should read STAFF/AFP via Getty Images)
Now playing
04:30
Pentagon report gives insight on White supremacists in active military
Now playing
03:57
GOP senator continues to push riot conspiracy theory
Now playing
02:08
Cabinet secretary explains why he took on challenging role
Rep. Debra Haaland (D-NM), President Joe Biden
PHOTO: Leigh Vogel/Pool/Getty Images
Rep. Debra Haaland (D-NM), President Joe Biden's nominee for Secretary of the Interior, testifies during her confirmation hearing before the Senate Committee on Energy and Natural Resource, at the U.S. Capitol on February 24, 2021 in Washington, DC.
Now playing
00:59
'We need to work together': Haaland responds to question on blind loyalty
Now playing
01:35
Laughter follows awkward moment between GOP leaders
PHOTO: AFP/Getty Images/CNN
Now playing
03:11
Cabrera: GOP suddenly cares about mean tweets ... just not Trump's
Now playing
03:20
Avlon on Ron Johnson: Hyperpartisan denial is a hell of a drug
WASHINGTON, DC - JANUARY 06: Pro-Trump supporters storm the U.S. Capitol following a rally with President Donald Trump on January 6, 2021 in Washington, DC. Trump supporters gathered in the nation
PHOTO: Samuel Corum/Getty Images
WASHINGTON, DC - JANUARY 06: Pro-Trump supporters storm the U.S. Capitol following a rally with President Donald Trump on January 6, 2021 in Washington, DC. Trump supporters gathered in the nation's capital today to protest the ratification of President-elect Joe Biden's Electoral College victory over President Trump in the 2020 election. (Photo by Samuel Corum/Getty Images)
Now playing
03:04
Capitol officials say riot was planned and involved white supremacists
Then-President Donald Trump addresses supporters during a Make America Great Again rally in Erie, Pennsylvania, October 20, 2020.
PHOTO: SAUL LOEB/AFP/Getty Images
Then-President Donald Trump addresses supporters during a Make America Great Again rally in Erie, Pennsylvania, October 20, 2020.
Now playing
02:44
What Trump's released tax records mean for DA's criminal case
Now playing
02:51
'This is incredible': Burnett explains Trump's reported offer to Kim Jong Un
From left, President Joe Biden, First Lady Jill Biden, Vice President Kamala Harris and her husband Doug Emhoff, bow their heads during a ceremony to honor the 500,000 Americans that died from COVID-19, at the White House, Monday, Feb. 22, 2021, in Washington. (AP Photo/Evan Vucci)
PHOTO: Evan Vucci/AP
From left, President Joe Biden, First Lady Jill Biden, Vice President Kamala Harris and her husband Doug Emhoff, bow their heads during a ceremony to honor the 500,000 Americans that died from COVID-19, at the White House, Monday, Feb. 22, 2021, in Washington. (AP Photo/Evan Vucci)
Now playing
05:45
Biden leads nation in mourning 500,000 US Covid-19 deaths
PHOTO: CNN
Now playing
01:06
Honig: Public won't see Trump's taxes unless this happens
(CNN) —  

The White House is preparing a draft proclamation for President Donald Trump to declare a national emergency along the southern border and has identified more than $7 billion in potential funds for his signature border wall should he go that route, according to internal documents reviewed by CNN.

Trump has not ruled out using his authority to declare a national emergency and direct the Defense Department to construct a border wall as Congress and the White House fight over a deal to end the government shutdown. But while Trump’s advisers remain divided on the issue, the White House has been moving forward with alternative plans that would bypass Congress.

“The massive amount of aliens who unlawfully enter the United States each day is a direct threat to the safety and security of our nation and constitutes a national emergency,” a draft of a presidential proclamation reads.

“Now, therefore, I, Donald J. Trump, by the authority vested in me by the Constitution and the laws of the United States of America, including the National Emergencies Act (50 U.S.C 1601, et seq.), hereby declare that a national emergency exists at the southern border of the United States,” the draft adds.

The draft was updated as recently as last week, a US government official told CNN.

RELATED: Senate blocks competing proposals to reopen government

According to options being considered, the administration could pull: $681 million from Treasury forfeiture funds, $3.6 billion in military construction, $3 billion in Pentagon civil works funds, and $200 million in Department of Homeland Security funds, the official said.

As lawmakers discussed a short-term measure to fund the government Thursday, Trump again raised the prospect of other ways to fund a border wall without congressional approval.

“I have other alternatives if I have to and I’ll use those alternatives if I have to,” he told reporters.

“A lot of people who wants this to happen. The military wants this to happen. This is a virtual invasion of our country,” Trump said.

The Defense Department referred a request for comment from CNN to the White House.

If the declaration is made, the US Army Corps of Engineers would be deployed to construct the wall, some of which could be built on private property and would therefore require the administration to seize the land, which is permitted if it’s for public use.

The administration’s plans acknowledge the possibility for lawsuits if they move forward with acquiring private property. The documents also reflect a sense of urgency with administration plans, noting that environmental reviews can be skipped and DHS can use waivers to bypass contracting laws.

If the President proceeds with the declaration, it’ll likely be challenged in court and by Democrats in Congress, as critics have argued that Trump cannot use the national emergency authority to free up taxpayer funds and build the border wall he has long promised his political supporters.

The question of legality and court challenges is still one of the main hang-ups in using executive action to secure the wall funding. Trump’s advisers have cautioned that taking that route would lead to certain legal challenge, meaning the wall construction would still be delayed.

The draft document cites Title 10 of the US Code, which allows Trump to unlock a stash of Pentagon funds that are earmarked but have no signed contracts for spending that money. That would give the President authority to pull from military construction funds and civil works projects, like infrastructure repair projects.

Rep. Dan Crenshaw, R-Texas, tweeted earlier this month that acting White House Chief of Staff Mick Mulvaney, “assured Texans that he understood the deep concerns about using Harvey relief funds for the border.” CNN previously reported that the Pentagon was asked to provide a list of those projects in anticipation of a national emergency.

The Pentagon has assisted the Department of Homeland Security in the past. For example, the Army Corps of Engineers, a federal agency within DOD that provides public engineering services, has helped evaluate prototypes of the border wall.

Options under consideration conceded that acquiring private property would take time. Even if voluntary, the land could take up to a year to be acquired. Land condemnation cases are known to take time because property owners have the right to sue. A national emergency declaration would not speed that process up, a government official says.

Customs and Border Protection has said that it would consider eminent domain in the future.

“It is always CBP’s preference to acquire property through a voluntary, negotiated sale. The Government will attempt to negotiate an offer to sell using survey data and value estimates gleaned from the surveying process,” reads an excerpt in a border wall Q&A on their site. “The Government will attempt to negotiate an offer to sell before moving forward with exercising eminent domain. However, if the Government and landowner are unable to reach a negotiated sale or if the Government is unable to obtain clean title, the Government will need to file an eminent domain action.”

CNN’s Kevin Liptak contributed to this report.