The US justice department has filed a lawsuit against Chicago, accusing local officials of impeding federal immigration enforcement efforts amid Donald Trump's drive to ramp up deportations.

The federal lawsuit is the first by Trump's Justice Department against states or municipalities that have sanctuary city policies.

Illinois Gov. JB Pritzker says the state has done nothing but follow the law, but the Department of Justice says the opposite — arguing that both Illinois and Chicago passed legislation that inhibited immigration enforcement in the state.