According to The New York Times, Chief of Staff John Kelly said Donald Trump promised his "big, beautiful wall" but never was "fully informed" of all the natural barriers that already exist in the area. Kelly allegedly had persuaded Trump to stop insisting on the wall adding the president's opinion on the barrier had "evolved."

After Kelly touched on the issue of whether the President would build the controversial wall of the US border with Mexico, Donald Trump went to his Twitter account to clarify and insist that the wall would be built and Mexico would pay for it. "The Wall is the Wall, it has never changed or evolved from the first day I conceived of it," Trump wrote "Parts of it will be, of necessity, see through and it was never intended to be built in areas where there is natural protection such as mountains, wastelands or tough rivers or water." 

 Even though Mexico has no intention of helping Trump erect his barrier, The U.S. President insisted that will happen "directly" or "indirectly." "The Wall will be paid for, directly or indirectly, or through longer term reimbursement, by Mexico, which has a ridiculous $71 billion trade surplus with the U.S.," Trump tweeted. "The $20 billion dollar Wall is 'peanuts' compared to what Mexico makes from the U.S. NAFTA is a bad joke!" referring to the North American Free Trade Agreement that former US President Bill Clinton, negotiated during the 1990s.

"We need the Wall for the safety and security of our country," he later added. "We need the Wall to help stop the massive inflow of drugs from Mexico, now rated the number one most dangerous country in the world. If there is no Wall, there is no Deal!"

On January 25, 2017, Trump signed the executive order to begin the construction of the border wall. Establishing a new vision to strengthen the borders of his country and increase efforts to deport some of the 11 million undocumented immigrants living in the United States. 

"A nation without borders is not a nation," Trump said during his speech at the headquarters of the Department of Homeland Security. "From today, the United States once again takes control of its borders."

In October 2017, eight prototypes of the possible border wall with Mexico were revealed; the mockups were 30 feet high and six-feet deep, four of them are made of concrete, and the four others are made of metal, concrete and other materials, and would be would be tested to determine which worked best in curbing illegal immigration and drug trafficking.

The Congress hasn't still approved the funds Trump's administration is asking for, that's why Trump continues to insist that Mexico will pay for the construction of the barrier between both countries.