Alan Gomez

USA TODAY

President Trump proposed a massive $4.8 billion increase in spending Thursday to combat illegal immigration, but his plan also includes a cut that stuns local law enforcement officials: a Department of Justice grant that helps pay the cost of jailing undocumented immigrants.

Throughout his campaign, Trump said he would help local communities enforce immigration laws and vowed to punish those that didn't — generally referred to as "sanctuary cities" — by withholding federal funds. Yet his budget would eliminate the State Criminal Alien Assistance Program, which would deny aid to localities that help enforce his ramped-up deportation program. The move would save the federal government $210 million this year.

That proposal came as a shock to officials in Miami-Dade County, which became the first jurisdiction in the country to shed its "sanctuary city" status by fully complying with Trump's immigration authorities. Mayor Carlos Gimenez ordered his jail to honor all requests by Immigration and Customs Enforcement (ICE) agents to detain undocumented immigrants, a controversial move that was approved by the county commission but led to sweeping protests in a county where a majority of residents are foreign-born.

"We are concerned," Michael Hernandez, a spokesman for the mayor, said Thursday. "We've been a good partner with federal immigration authorities. We expect them to be good partners with us."

The grants reimburse local jails for detaining for at least four days undocumented immigrants who committed one felony or two misdemeanors. Since 2000, the program has provided funding to hundreds of local jails.

Asked about the cut on Thursday, White House press secretary Sean Spicer said the budget proposes other ways to help local officials. "We increased the amount of money for detention facilities for folks who come into the country illegally," he said, referring to a $1.5 billion increase in spending to expand federal detention facilities, transportation and deportation of undocumented immigrants.

But local officials said none of that new money will help pay for all the undocumented immigrants who may end up in their jails.

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Yuma County (Ariz.) Sheriff Leon Wilmot said the only problem with the grant program is that it was woefully underfunded.

Wilmot has worked with Arizona's 14 other sheriffs for almost a decade to show how much they spend jailing undocumented immigrants. Since 2009, he said, the federal government owes Arizona sheriffs more than $310 million. That doesn't include medical costs for inmates, who may be malnourished, injured and sick after they make the dangerous trek across the southwest border.

Wilmot figured things would change under Trump, who won the sheriff's support during the presidential campaign because of his vows to beef up immigration enforcement.

Now, "I would say that I'm miffed," he said. "That's something we should be fully funding instead of cutting. I don't care what administration it is. If we have to pay those bills, they need to reimburse us."