WASHINGTON - Huge crowds are expected to hit the streets Saturday from New York to San Francisco to vent their anger over President Donald Trump's hardline policies at nationwide "No Kings" protests slammed by Republicans as "Hate America" rallies.

More than 2,700 demonstrations are planned coast to coast, from big cities to small towns, and even near Trump's Mar-a-Lago residence in Florida, where he is spending the weekend. Organisers say they are expecting millions to attend.

Those numbers would match the massive turnout at similar events on 14 June, Trump's birthday and the day of a giant military parade in the US capital, in outrage over the Trump administration's crackdown on undocumented migrants and its deployment of National Guard troops to Los Angeles.

Since then, Trump - who returned to the White House in January - has ordered National Guard troops into Washington and Memphis. Planned deployments to Chicago and Portland, Oregon have so far been blocked in the courts.

Demonstrators are also up in arms over Trump's attacks on the media, prosecutions of his political opponents and a host of other actions they see as authoritarian.