The president, who constantly plays to his conservative base, ended his tweet with the kind of nationalistic immigration rhetoric that roils Democratic lawmakers: "We need great people coming into our Country!"
US House Speaker Paul Ryan said that $1.6bn had already been agreed on for the wall, and lawmakers were mulling another request for $5bn.
"The only things the Democrats do well is "Resist, ' which is their campaign slogan, and "Obstruct.' Cryin" Chuck Schumer has nearly 400 great American people that are waiting 'forever" to serve our Country!" He added that money for the wall was "not a question of if, it's a question of when".
"There are a lot of things we shouldn't have had in this bill but we were, in a sense, forced if we want to build our military, we were forced to have", Trump said in March.
The president also insists that all immigration should be based on applicants demonstrating they represent valuable assets to the country, rather than be based on the diversity visa-lottery program and family ties.
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Injury, and also has to go back'. "Antonio Valencia comes from holiday, I think too much holiday for him". "You can not imagine how much I have enjoyed these two weeks with these guys".
However, a disruption in federal government operations could backfire on Trump if voters blame Republicans, who control Congress, for the interruption in services.
Trump's shutdown warning - which he has made before - escalates the stakes ahead of a September 30 government funding deadline, a political showdown before the November midterm elections that Republican congressional leaders had hoped to avoid. The Senate remains in session and is set to take a one-week break the week of August 6, then returning for the rest of the month.
Democrats have long opposed financing Trump's wall but don't have enough votes by themselves to block House approval of that amount, but they do have the strength to derail legislation in the closely divided Senate.
The $5 billion is well above the $1.6 billion in the Senate version of the bill, which would finance the Homeland Security Department. According to Politico, Trump was "receptive" to their plan.
Trump's Twitter threat introduced a fresh wild card for congressional negotiators to deal with as the remaining legislative days tick down before government funding runs out - an explosive prospect for both parties with just 100 days until the midterm elections.