In a fiery speech to hundreds of law enforcement officers, the acting director of U.S. Immigration and Customs Enforcement excoriated the political enablers of illegal immigration on Wednesday, saying he’ll “never back down” from safeguarding the border.

Speaking at the Border Security Expo in San Antonio, Thomas Homan singled out sanctuary cities and the ongoing congressional debate over so-called “Dreamers.”

“If we get a clean DACA bill, shame on all of us,” Homan said, referring to the Obama administration’s contentious Deferred Action for Childhood Arrivals program. "You can’t address DACA and reward people that brought children here illegally and not address underlying reasons of DACA.”

Homan, who said that he “100 percent support[s] the wall,” added that he is “sick and tired of the vilification of the men and women of ICE and the Border Patrol,” according to multiple accounts of his speech.

“If you violate the laws of this country, if you enter illegally, which is a crime, it’s not going to be OK anymore,” Horman said.

Sanctuary cities, Homan charged, endanger federal officers because they often force agents to make arrests in homes and workplaces – rather than controlled environments, like state jails.

“If you violate the laws of this country, if you enter illegally, which is a crime, it’s not going to be OK anymore." — Acting ICE Director Thomas Homan

"They [sanctuary cities] bankroll the very criminal organizations that have killed Border Patrol agents and killed special agents in ICE," Homan said, according to an account of his speech in the Washington Examiner.

"It irritates me that a politician who has never held a badge and a gun, who doesn’t understand what we do every day, makes a decision of putting their own political careers ahead of the health and safety of a law enforcement officer," he said. "A shame!"

The approximately 40-minute speech came on the same day that ICE formalized a policy to send deportation agents to federal, state and local courthouses to make arrests.

The two-page directive said ICE will enter courthouses only for specific targets, such as convicted criminals, gang members, public safety threats and immigrants who have been previously deported or ordered to leave.

Family, friends and witnesses won't be picked up for deportation but ICE leaves a caveat for "special circumstances."

The policy, signed by Homan, says immigration agents should generally avoid arrests in non-criminal areas of the court, like family court and small claims, unless it supervisor approves.

ICE — in a not-so-subtle jab at sanctuary cities— said "increasing unwillingness of some jurisdictions to cooperate with ICE in the safe and orderly transfer of targeted aliens inside their prisons and jails has necessitated additional at-large arrests."

The Associated Press contributed to this report.