A federal judge in Oregon has temporarily blocked President Donald Trump's administration from deploying the National Guard in Portland.

US District Judge Karin Immergut issued the order on Saturday in a lawsuit brought by the state and city.

The War Department (Defense Department) had said it was placing 200 members of Oregon's National Guard under federal control for 60 days to protect federal property at locations where protests are occurring or likely to occur after Trump called the city "war-ravaged."

Democratic Oregon Attorney General Dan Rayfield's office filed the lawsuit on September 28, a day after Trump said he would send troops to Portland.

The case was initially assigned to US District Judge Michael Simon, an appointee of Democratic President Barack Obama.

He recused himself after the Trump administration raised concerns about comments made by his wife, a congresswoman, criticising the troop deployment.

The case was reassigned to Immergut, who was appointed by Trump during his first term in office.

Oregon officials said that description was ludicrous. The US Immigration and Customs Enforcement building in the city has recently been the site of nightly protests, which typically drew a couple of dozen people in recent weeks before the deployment was announced.