Trump administration officials said Monday they're crafting a new legislative package aimed at closing immigration "loopholes," hours after the president called on Republicans in Congress to immediately pass a border bill using the "Nuclear Option if necessary" to muscle it through.

"Border Patrol Agents (and ICE) are GREAT, but the weak Dem laws don't allow them to do their job. Act now Congress, our country is being stolen!" President Donald Trump wrote in a series of sometimes-misleading tweets, fired off after returning from a holiday weekend spent in Florida with several immigration hardliners.

Trump also declared protections for so-called Dreamer immigrants "dead," claimed the U.S. has "no effective border laws" and warned Mexico to halt the passage of "caravans" of illegal immigrants or risk retribution.

"They must stop the big drug and people flows, or I will stop their cash cow, NAFTA. NEED WALL!" he wrote.

Trump has been seething over immigration since realizing the major spending bill he signed last month barely funds the "big, beautiful" border wall he has promised his supporters. The $1.3 trillion funding package included $1.6 billion in border wall spending, but much of that money can be used only to repair existing segments, not to build new sections.

Among the measures the administration is pursuing: ending special safeguards that prevent the immediate deportation of children arrested at the border and traveling alone. Under current law, unaccompanied children from countries that don't border the U.S. would be placed under the supervision of the Department of Health and Human Services and undergo often-lengthy deportation proceedings before an immigration judge instead of being deported.

The administration is also pushing Congress to terminate a 1997 court settlement that requires the government to release children from custody to parents, adult relatives or other caretakers as their cases make their way through immigration court. Officials complain that many children never show up at their hearings.

The proposals appear the same as those included on a White House immigration wish list that was released in October but failed to gain traction during negotiations over the border wall. Such proposals are likely to face opposition from moderate Republicans and Democrats going into the midterm elections. But Trump appears intent on ensuring the issues remain at the forefront of public conversation, even though the omnibus was widely seen as the last major legislation likely passed this year.

In his Easter weekend tweets and comments, Trump continued to blame Democrats for killing the Obama-era Deferred Action for Childhood Arrivals program despite the fact that he was the one who moved to end the program. He also claimed DACA, which has provided temporary protection from deportation and work permits to hundreds of thousands of young people, is luring people to cross the border illegally, even though the program — and most proposals to replace it — have never been open to new arrivals.

Trump spent much of the weekend at his Mar-a-Lago club, having meals with his family, watching cable news shows and rubbing elbows with conservative commentators including Fox News host Sean Hannity, according to several club members. Also spotted at the club: championship golfer Dustin Johnson, MyPillow maker Michael J. Lindell, boxing promoter Don King and former New York Police Commissioner Bernie Kerik.

Staffers with Trump over the holiday included policy adviser Stephen Miller, one of the chief architects of the administration's anti-immigration policies, but not his chief of staff John Kelly or his elder daughter, Ivanka, both considered more moderate influences.

Trump's past calls to use the "nuclear option" — changing the Senate rules to require a simple majority of 51 votes to override a rule instead of 60— have been repeatedly dismissed by Senate Majority Leader Mitch McConnell, who argues Republicans will welcome the filibuster if they return to being the Senate minority. The current split is 51-49 favoring Republicans.

Notably, Trump's favored DACA solution mustered only 39 votes in the Senate, meaning it couldn't have passed even if the Senate did approve the changes.

Trump's tweets calling on Mexico to halt "caravans" filled with immigrants in the country illegally came after a "Fox & Friends" report early Sunday that featured the leader of the union representing border patrol agents predicting that those in the caravan would create havoc and chaos in the U.S. as they wait for immigration reform.

About 1,100 migrants, many from Honduras, have been marching along roadsides and train tracks in the southern Mexican state of Oaxaca.

These "Stations of the Cross" migrant caravans have been held in southern Mexico for at least the last five years. They began as short processions of migrants, some dressed in biblical garb and carrying crosses, as an Easter-season protest against the kidnappings, extortion, beatings and killings suffered by many Central American migrants as they cross Mexico.

Individuals in the caravans often try to reach the U.S. border but usually not as part of the caravan. The caravans typically don't proceed much farther north than the Gulf coast state of Veracruz. The current march is scheduled to end this month with a conference on migration issues in the central Mexican state of Puebla.