President Trump tweeted Saturday to support and defend key national-security initiatives -- arguing refugees from “dangerous” countries are streaming into the U.S. while courts halt his travel ban and suggesting that he can undercut the projected, multi-billion-dollar cost for his border wall.

“I am reading that the great border WALL will cost more than the government originally thought, but I have not gotten involved in the design or negotiations yet. When I do, just like with the F-35 FighterJet or the Air Force One Program, price will come WAY DOWN!,” Trump said over two, 140-character-maximum tweets.

The Department of Homeland Security said this past week that the U.S.-Mexico border wall will cost roughly $21.6 billion and take three-and-a-half years to build.

Trump, a former businessman and real estate magnate, is known for his deal-making, in fact having written a book in 1987 titled “The Art of the Deal.”

Earlier Saturday, Trump tweeted about his Jan. 27 executive order that banned refugees from seven mostly Muslim countries. Federal courts temporarily halted the ban, then effectively denied the Justice Department’s legal request to lift it.

“Our legal system is broken!” Trump tweeted. “77% of refugees allowed into U.S. since travel reprieve hail from seven suspect countries." (WT) SO DANGEROUS!”

The Republican president was apparently referring to a Washington Times story.

The most updated numbers from the State Department show the percentage closer to 72 percent for the week of Feb. 3 ­– 11.

Syria: 402

Iraq: 340

Iran: 115

Somalia: 155

Sudan 37

Libya: 0

Yemen: 0

Total: 1,049