Attorney General Jeff Sessions claimed the U.S. would save billions of dollars in the long-term as a result of building a southern border wall despite the initial $21 billion cost to build it, during a Sunday interview on ABC.

"I do believe this wall, this barrier is going to be essential in ending the illegality. It will save us billions of dollars because the numbers of people that are coming will be reduced dramatically; the amount of drugs entering our country will be reduced; the amount of people we are housing in detention centers will be declining," Sessions told "This Week" host George Stephanopoulos.

"We are gonna get people out of the country to these countries that aren't taking them back after they're due to be deported. It's going to save us hundreds of millions — billions of dolllars," Sessions added.

Congress is on deadline to pass a spending bill deal by midnight Friday. While Trump's budget chief, Mick Mulvaney, wouldn't say Sunday if Trump would sign a spending bill without funding for a border wall, Homeland Security Secretary John Kelly warned on CNN that Trump will shut down the federal government if he doesn't get the funding he's looking for.

Although Sessions is not a part of budget negotiations in Congress or involved in talks with Mexican government officials, he said the southern country is not expected to appropriate money for the U.S. project.

"I don't expect the Mexican government to appropriate money for it, but there are ways that we can deal with our trade situation that we can create revenue to pay for it," Sessions said.

In addition, Sessions proposed reining in wasteful spending, citing an Obama era Treasury Department report that found the U.S. spends $4 billion annually in excess payments and tax credits to people who are "mostly Mexicans."