Six sheriffs from some California's biggest counties met with Sen. Jeff Sessions Tuesday on Capitol Hill to back his nomination for attorney general, just a day before his expected Senate confirmation, and as President Trump is threatening to withhold federal funding to cities that shelter illegal immigrants.

Sheriff John McMahon of San Bernardino, the site of the December 2015 terrorist attack that killed 14 people, was strongly enthusiastic about Sessions.

"He wants to bring law enforcement together with the U.S. attorney general's office and [have] everybody meet and talk about collaborative solutions to problems that we're all facing locally, not only just in California but across the entire nation," McMahon told the Washington Examiner. "And a good, close relationship with the attorney general's office makes a big difference in what we're able to do every day."

After their meeting, the sheriffs said they are seeking Sessions' support once he becomes attorney general as expected on Wednesday. That includes working together on several California-specific problems that are tying their hands when it comes to keeping illegal immigrants convicted or charged with major crimes detained in order to work with federal immigration authorities.

The sheriffs said they are already severely limited in how long they can hold illegal immigrants before they are forced to release them. California lawmakers also are advancing measures that would further restrict their ability to work with Immigration and Customs Enforcement to detain illegal immigrants charged but not convicted of crimes.

"Everyone in this room has the same issue," McMahon said.

When inmates are booked into county facilities, local authorities send their fingerprint to ICE to determine whether they are wanted for deportation based on their charges and past records. If ICE wants to come pick them up, they have a very short window — less than 48 hours — in order to do so.

"If our bus goes to the place to release them and ICE is not there, that person walks off the bus and is back in the community — we no longer have the ability to hold them for 48 hours like we used to," McMahon said. He was referring to a court decision which said holding these people violates their 4th Amendment rights against unreasonable search and seizures.

"All we're asking, and not just here but all over, is a process to allow a warrant, a probable cause declaration, some type of judicial review that will give us the ability to hold them for up to 48 hours so ICE has time to come pick them up," he said.

Geoff Dean, the sheriff of Ventura County, said many of the immigrants in question are either convicted or face charges for serious crimes such as murder, rape and assault with deadly weapon.

"They are a small percentage in my county in Ventura, .08 percent of our total inmate population. It's not like we're deporting a lot of people — last year it was people charged with homicide to multiple DUIs, rapes, everything," he said. "It seems common sense. I'm not sure anybody would want someone who has someone who has committed a murder, rape, or child molests in the country illegally to stay."

Others who participated in the meeting were Sheriffs Donny Youngblood of Kern County, Steve Freitas of Sonoma County, Scott Jones of Sacramento County and David Livingston of Contra Costa County, and Undersheriff Don Barnes of Orange County.

The meeting between Sessions and the California county sheriffs came amid a war of words between Democratic leaders in the state and Trump.

During an interview with Fox News' Bill O'Reilly Sunday, Trump said California "in many ways is out of control as you know."

He specifically said the state's consideration of legislation to create statewide sanctuary for people living in the country illegally is "ridiculous" and threatened to withhold federal funds as a result.

"I don't want to defund anybody. I want to give them the money they need to properly operate as a city or a state," Trump said. "If they're going to have sanctuary cities, we may have to do that. Certainly. that would be a weapon."

Leaders of the state Legislature pushed back Monday, pointing to the state's economy and strong job growth as important contributions to the nation, according to the Associated Press.

"If this is what Donald Trump thinks is 'out of control,' I'd suggest other states should be more like us," said Assembly Speaker Anthony Rendon, D-Paramount.