Washington DC - Donald Trump's administration on Thursday sued the so-called "sanctuary" city of Chicago and the state of Illinois for allegedly blocking the president's efforts to deport undocumented migrants.

The lawsuit seeks to overturn measures passed in recent years that prohibit police from arresting people based on their immigration status and limit what information can be shared with federal authorities.

Los Angeles and New York City, which also have large immigrant communities, are among other major cities with similar rules.

Thursday's filing cites Trump's declaration of a "national emergency" on the southern US border and an executive order he signed stating that many undocumented migrants present "significant threats to national security and public safety."

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"Further exacerbating this national crisis, some of these aliens find safe havens from federal law enforcement detection in so-called Sanctuary Cities where they live and work among innocent Americans, who may later become their crime victims," it says.

Trump has insisted that undocumented migrants are disproportionately responsible for crime, despite research showing US citizens commit more offenses per capita.

The lawsuit, filed in an Illinois court, calls for an injunction on the enforcement of the measures on the basis that they violate the supremacy of federal law.

It alleges that "countless criminals" have been released back into Chicago due to officials' failure to fully cooperate with federal immigration laws.

Trump, who has vowed large-scale deportations of undocumented migrants, has long promised legal action against sanctuary states and cities, which are largely Democrat-led.

"Sanctuary cities are a sanctuary for criminals," Trump's so-called border czar, Tom Homan, told reporters at the White House on Thursday. "We're going to hold sanctuary cities accountable."

Homan dismissed defenses that sanctuary policies allow migrants who are witnesses or victims of crimes to cooperate with local police without fear of deportation.

"That is such crap, because the victims and witnesses of crime don't want the public safety threat released in their communities. That's just ridiculous," he said.

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A spokesman for the office of Illinois Governor JB Pritzker said they "look forward" to challenging the lawsuit in court.

"Unlike Donald Trump, Illinois follows the law," they said in a statement, adding that the Trump administration is making it "more difficult to protect the public, just like they did when Trump pardoned the convicted January 6 violent criminals."