The president said that a wall or a barrier must be built along the US southern border with Mexico, while signaling a willingness to accept a steel barrier instead of a concrete wall by saying that "steel instead of concrete is fine".
Trump's tweet came shortly after The New York Times reported that the White House had requested prime-time television slots on Tuesday night for Trump to make an Oval Office address on the border wall and government shutdown.
For instance, during a news conference on Friday, Trump claimed that predecessors in the White House had told him that they would have supported a border wall, but that was contradicted by spokespersons for the living ex-commanders in chief. There, Democratic sources familiar with the meeting said that the administration "doubled down" on its proposal, which initiated the shutdown on December 22.
"It (the shutdown) is a very important battle to win".
The proposed wall is reportedly going to be made from steel, which Trump told reporters would be "less obtrusive" and "stronger".
Trump says he's still mulling declaring a national emergency to try to circumvent Congress.
"I am sure that the people that are on the receiving end will make adjustment, they always do", Trump said. He must take the issue directly to Americans, who seem largely bewildered by the rationale for the current government shutdown - in reality, Democrats simply refuse point blank to fund the wall to the tune of $5 billion.
Later in the afternoon, Trump told reporters, "We're looking at a national emergency because we have a national emergency". It may have been a tactic created to push Democrats to do a deal but Trump's opponents said such a move would be, in the words of congressman Adam Schiff, a "non-starter", subject to fierce opposition and legal challenges.
For their part, Democrats said there was no progress as the shutdown entered its 16th day, and asked again that the government be reopened before negotiations on border security money begin. An estimated 800,000 federal employees throughout the country have either been furloughed and are going without a salary or, if deemed essential, are working without getting paid.
"The Army Corps of Engineers is dialed in on doing this cost effectively and with the right amount of urgency as to where we can build additional stand-up walls quickly and then get after the threat", Shanahan said.
"We have a five-month-old son so we have about a month left before we're going to have to start having those hard conversations about what to do next", he said.
"This shutdown could end tomorrow and it could also go on for a long time", Trump said.
She added that it is "incomprehensible" that Democrats who agree with Trump on the need for border security would not agree to his demand for wall funding.
Former White House communications director Joe Lockhart on Twitter advised TV networks to "demand to see the text in advance and if it is not truthful either don't air it or fact check it live on lower third".
During a meeting on Saturday with Vice President Pence, White House adviser Jared Kushner, Homeland Security Secretary Kirstjen Nielsen, and Mulvaney, Democrats pushed for details on how the president will spend the money he has requested.
Many workers, but by no means all, are likely to get back pay when the shutdown is resolved.