President Trump doubled down Thursday on his demand for any immigration bill that codifies an Obama-era immigration program to include funding for his promised wall along the southwest border, even as Democrats continue to argue that such a provision is a non-starter.

"We need a physical border wall. We're going to have a wall — remember that, we're going to have a wall — to keep out deadly drug dealers, dangerous traffickers and violent criminal cartels. Mexico's having a tremendous problem with crime and we want to keep it out of our country," Trump told Republican senators during a meeting at the White House on Thursday.

Lawmakers are scrambling to strike a bipartisan immigration deal before the Deferred Action for Childhood Arrivals program expires in March on Trump's orders. DACA extends temporary legal protections to roughly 800,000 undocumented immigrants who were brought to the country illegally as children.

"We need to ensure our immigration officers finally have the resources, tools and authorities that they desperately deserve and need to save and protect American lives," Trump said. "These are incredible people, they've been with me right from the beginning and they love what we're doing."

"That's why our position has been clear, and very clear from the beginning. Any legislation on DACA must secure the border with a wall, it must give our immigration officers the resources they need to stop illegal immigration and also to stop visa overstays and, crucially, the legislation must end chain migration," the president added. "It must end the visa lottery. Dangerous, and I think many of the Democrats agree with us on that now."

The White House began increasing its focus late last year on the diversity visa lottery program after an alleged terrorist who entered through the system attacked a New York City sidewalk on Halloween, killing eight people and injuring more than a dozen others.

"The lottery system is a disaster," Trump said. "They put down their probably worst people — who knows? — but they're not looking to get rid of their best people, so they put their worst people in a hopper and we're picking out the people, and then we find out, what do we have? It's not a good situation, so we're going to end it. The lottery system has to be laughed at by countries outside of our country when they send these people in."

Trump has said he wants to see the immigration system focus more heavily on the merits of applicants.