Donald Trump has criticised America's "broken" court system after he was blocked from deporting illegal migrants brought to the country while children.

The US president’s decision to rescind protections implemented by his predecessor Barack Obama was overruled by a federal judge in California.

Around 800,000 “dreamer” migrants smuggled into the United States when children were due to be stripped of their right to work legally on March 5.

Mr Obama had granted the protections in 2012 through Deferred Action for Childhood Arrivals program, which is known as DACA.

Last September, Mr Trump, who adopted a hard line on immigration during his election campaign, dubbed the move unconstitutional and announced he would end the program.

However Judge William Alsup of Federal District Court in San Francisco ruled on Tuesday that the administration must “maintain the DACA program on a nationwide basis” while a legal challenge progresses.