WASHINGTON — President Trump used extraordinarily harsh rhetoric to renew his call for stronger immigration laws Wednesday, calling undocumented immigrants "animals" and venting frustration at Mexican officials who he said "do nothing" to help the United States.

“We have people coming into the country or trying to come in, we're stopping a lot of them, but we're taking people out of the country. You wouldn't believe how bad these people are," Trump said.

"These aren't people. These are animals."

Trump's comments came in a freewheeling, hour-long White House meeting with local California leaders opposed to so-called "sanctuary city" policies. "California's law provides safe harbor to some of the most vicious and violent offenders on Earth, like MS-13 gang members putting innocent men, women, and children at the mercy of these sadistic criminals," he said.

His comment about "animals" came after Fresno County Sheriff Margaret Mims complained that state law forbids her from telling U.S. Immigration and Customs Enforcement about undocumented immigrants in her jail — even if she suspects they're part of a gang.

"There could be an MS-13 member I know about. If they don’t reach a certain threshold, I cannot tell ICE about it," she said.

Trump's remarks were reminiscent of his first press conference as a presidential candidate in 2015, when he said the United States had become a "dumping ground" for people other countries didn't want.

"When Mexico sends its people, they're not sending their best," he said then. "They're bringing drugs. They're bringing crime. They're rapists. And some, I assume, are good people."

Trump has been particularly vocal in opposing so-called "sanctuary city" policies, in which some jurisdictions have refused to fully cooperate with federal immigration authorities. On Wednesday, he highlighted California cities who do cooperate, inviting mayors and sheriffs opposed to the state's predominant policy.

"Each of you has bravely resisted California's deadly and unconstitutional sanctuary state law," Trump told them.

In other comments, Trump:

► Called for Attorney General Jeff Sessions to investigate Oakland Mayor Libby Schaaf for warning undocumented immigrants of an upcoming sweep by immigration agents. "You talk about obstruction of justice, I would recommend that you look at obstruction of justice for the mayor, Jeff," the president said.

► Expressed frustration at his southern neighbor for not doing more to stop the flow of refugees and immigrants into the United States. "Mexico does nothing for us, they do nothing for us. Mexico talks, but they do nothing for us, especially at the border," he said. "Certainly don’t help us much on trade."

► Blamed Democrats for a policy of separating children from their parents when undocumented families enter the United States.

"I know what you're going through with families is very tough," he told Homeland Security Secretary Kirstjen Nielsen. "But those are the bad laws the Democrats gave us. We have to break up families. The Democrats gave us that law. It's a horrible thing we have to break up families."

Alan Gomez reported from Miami. David Jackson contributed.