Former President Trump will use local police to implement his plan for the mass deportation of undocumented migrants if he's elected, the Republican primary frontrunner said during an interview on Fox News Thursday.

The big picture: Trump, who visited the U.S.-Mexico border on the same day as President Biden Thursday, has vowed to launch the "largest deportation operation in American history" if he's elected president for a second term in November.

What he's saying: "We have to deport a lot of people, and they have to start immediately," Trump said during his interview in Eagle Pass, Texas, on Fox News' "Hannity."

• Trump told Fox News host Sean Hannity that he would give "immunity" to police "to give the job they have to do" and said the officers understand who the migrants are.
• "It's going to be the local police are going to turn them over, and we're going to have to move them back to their country," he added.

What we're watching: A judge on Thursday temporarily paused a Texas law that would allow local authorities and judges to arrest and deport immigrants they suspected of crossing the border into the U.S. without legal authorization, which was due to take effect on March 5.

• Texas Gov. Greg Abbott has vowed to appeal the ruling in favor of the Justice Department and civil rights groups, which argued in their lawsuit that the legalization was unconstitutional and could lead to racial profiling.

State of play: Biden used his second U.S.-Mexico border visit as president, in Brownsville, Texas, to call on Trump to "join" him in working on passing the toughest immigration law in decades.

• Trump said during his visit to Eagle Pass that Biden has the "blood of countless innocent victims" on his hands as he claimed the U.S. was being "overrun by the Biden migrant crime" — despite studies showing immigrants are less likely to commit crimes than other U.S. residents.

Zoom out: Polls suggest Americans consider immigration to be the most important issue in the U.S.

• Biden was elected president after campaigning on ending Trump-era border policies, but since then there's been a global humanitarian crisis that's resulted in tens of millions of people being forcibly displaced.
• The president has since hardened his immigration policy and is considering signing an executive order that would restrict the ability of migrants to claim asylum.
• Trump is again taking a hardline approach to the issue, as he did during his 2016 election campaign.

Go deeper: Trump's promised mass deportations would be met with resistance

Editor's note: This article has been updated with new details throughout.