President Donald Trump said undocumented immigrants should be immediately deported and denied due process once they enter the country.

The president, who tweeted Sunday morning during his drive to Trump National Golf Club, went one step further than his administration’s “zero tolerance” policy, which demands every immigrant who comes to the United States illegally should be criminally prosecuted.

Trump’s hasty decision last week to use an executive order to try to end family separation, which happened as a result of his administration’s “zero tolerance” policy, sparked confusion and chaos ahead of upcoming congressional votes on immigration.

“We cannot allow all of these people to invade our Country,” he tweeted. “When somebody comes in, we must immediately, with no Judges or Court Cases, bring them back from where they came. Our system is a mockery to good immigration policy and Law and Order.”

“Our Immigration policy, laughed at all over the world, is very unfair to all of those people who have gone through the system legally and are waiting on line for years!" the president added. "Immigration must be based on merit - we need people who will help to Make America Great Again!”

Last week, the Trump administration’s family separation policy sparked a national outcry. The White House struggled to defend the policy in the wake of backlash like the kind seen in the aftermath of the travel ban on people from Muslim-majority countries.

Trump has said he does not want to see families separated, but noted that he was encouraged to fix the situation on the border at the urging of first lady Melania Trump and his daughter, Ivanka.

But despite issuing his executive order, Trump has maintained that his “zero tolerance” policy, introduced by Attorney General Jeff Sessions in April, will remain. At the Nevada Republican Conference in Las Vegas on Saturday, Trump continued to advocate for the “zero tolerance” policy and said that he wants immigration based on merit.

“By the way we want people to come into the county, but on merit. We want a merit-based system,” Trump said. “We need people to come in but they need to love this country to help make America great again."

But denying immigrants, regardless of their legal status, the right to due process could violate the law.

The American Civil Liberties Union quickly released a statement condemning the proposal soon after Trump tweeted.

“What President Trump has suggested here is both illegal and unconstitutional. Any official who has sworn an oath to uphold the Constitution and laws should disavow it unequivocally,” Omar Jadwat, director of the ACLU’s Immigrants’ Rights Project said.

Sen. Lindsay Graham, R-South Carolina, and Sen. Ted Cruz, R-Texas, have both said more judges are needed along the border to handle the influx of immigrants and cases as a result of the “zero tolerance” policy. Last week, Cruz introduced legislation that would help handle asylum claims at the border by doubling the number of federal immigration judges to 750.

The legislation also calls for the creation of more shelters to house families together.

Still, Trump has rejected calls for additional immigration judges at the border, instead calling for strong security and a border wall.

"We are the only people, people walk in and put a foot in, 'Please, would you like to register?' Other countries say get the hell out of here. They do that. They have to do that. We say, you know, they want to hire 5,000 more judges so that a person puts the toe in the land we have to go to trial,” Trump said in Las Vegas. “This is crazy what we are doing. I don't want judges, I want border patrol, I want ICE.”