NICOLA Sturgeon has hit out at Donald Trump for telling Democrat congresswomen to "go back" to where they came from.

As his administration launched a nationwide crackdown on illegal immigration, the US President launched a Twitter tirade against the congresswomen, who have been highly critical of his immigration policies, telling them: "You can't leave fast enough."

The "progressive' Democrat Congresswomen" mentioned in Trump's tweet appears to be a reference to a group of liberal, recently elected women, who have become known as "the squad."

They include Alexandria Ocasio-Cortez of New York, Minnesota Congresswoman Ilhan Omar, and Rashida Tlaib of Michigan.

Sturgeon said Trump's comments are "not OK".

She added: "The President of the United States telling elected politicians - or any other Americans for that matter - to ‘go back’ to other countries is not OK, and diplomatic politeness should not stop us saying so, loudly and clearly."

As it reached morning in Washington, Trump repeated his attacks on the congresswomen.

He tweeted: "When will the Radical Left Congresswomen apologize to our Country, the people of Israel and even to the Office of the President, for the foul language they have used, and the terrible things they have said. So many people are angry at them & their horrible & disgusting actions!"

Late on Saturday night, agents from Immigration and Customs Enforcement began the first of a series of raids, which will take place in at least 10 cites over several days.

They planned to arrest at least 2100 illegal immigrants, including families, who are on so-called "rocket dockets," which means they have already been sent court orders telling them to leave the country.

An estimated 11 million illegal immigrants are currently in the United States, one million of whom have been sent final removal orders. The 2000, mostly from Central America, are among those one million.