Philadelphia is among nine local or state governments that received a warning in writing Friday from the Department of Justice about funding tied to "sanctuary city" policies.

The letter reiterated what U.S. Attorney General Jeff Sessions implied at a press conference earlier this month: Communicate with immigration agencies or face possible punitive action in the form of federal funding.

Like Sessions's warning, the letter addressed to Mayor Jim Kenney from Acting Assistant Attorney General Alan Hanson hinged on a requirement in federal law, known in immigration circles as "1373," which is titled "Communication between government agencies and the Immigration and Naturalization Service."

It obliges local governments to cooperate in certain information-sharing with federal agencies like Immigration and Customs Enforcement.

Hanson's letter states that Philadelphia is required to cooperate under 1373 as per its grant agreement with the DOJ's Office of Justice Programs, which is one of the federal government's largest funding sources for local law enforcement.

The letter also states:

As your grant agreement makes clear, this documentation must be accompanied by an official legal opinion from counsel that adequately supports the validation and must be submitted to OJP no later than June 30, 2017. Failure to comply with this condition could result in the withholding of grant funds, suspension or termination of the grant, ineligibility for future OJP grants or subgrants, or other action, as appropriate.

A spokeswoman for Kenney said, "We have been aware of the requirement to certify since 2016, and we believe there is nothing in our current policy that prohibits us from certifying."

When Sessions issued his warning, Kenney spokeswoman Lauren Hitt said Sessions was "threatening to take away money from the police department for what amounts to nothing more than good police work. Undocumented residents and their family members are much less likely to call law enforcement when they are a witness to or a victim of a crime if they know that the police will turn them in to ICE. And if residents can’t call the police, then it is extremely difficult to get criminals off the street. If we are forced to change Philadelphia’s policy on this, all of our residents will be less safe.”

The letter, like Sessions's comments, do not address what many associate more closely with sanctuary cities: releasing immigrants who have ICE detainer warrants.

On its municipal website, Philadelphia describes how it handles information-sharing and ICE detainers:

In Philadelphia, we cooperate fully with all law enforcement agencies, including federal agencies, in connection with criminal investigations and apprehension of those accused of crimes. We also do not stop ICE from arresting Philadelphians whom they believe are undocumented. We do require that our police officers not ask about the documentation status of those they encounter. We only allow our Prison System to comply with ICE’s requests to turn over a detainee if they have a federal warrant.

In addition to the building pressure from the Trump administration, a state lawmaker from Northeast Philadelphia has introduced legislation that could potentially prevent Pennsylvania from providing funding to cities that don't comply with immigration authorities.

State Rep. Martina White, a Republican, introduced a bill in October that would impose funding restrictions on any "municipality of refuge."

A state Senate bill called the Municipal Sanctuary and Federal Enforcement (SAFE) Act that also would implement funding restraints on places like Philadelphia has been deemed "a more imminent threat" than potential actions by the Trump administration.

"Last fiscal year, the City received a total of about $790 million from the state. The state bill applies to all state grant funding. It’s unclear what falls under that category at this time. Large portions of this money are for reimbursement for carrying on duties the state wants and needs us to provide," the city's webpage on the sanctuary city status reads. "This bill is not just about Philadelphia. It defines sanctuary cities so broadly that it also jeopardizes state funding for a host of jurisdictions well beyond the 18 other ones that have been identified as sanctuary cities. Cutting critical state funds for all sanctuary cities and other jurisdictions across the state would impact every Pennsylvanian."