Donald Trump has been slammed as "cruel and wrong" by his predecessor Barack Obama.

In a rare public intervention since he left the White House, Mr Obama took issue with Mr Trump over his rescinding of an amnesty for 800,000 people brought to the United States illegally as children, who have become known as the "Dreamers".

Mr Obama, who first established the amnesty, said: "This is about young people who grew up in America. These Dreamers are Americans in their hearts, in their minds, in every way apart from on paper.

"To target these young people is wrong because they have done nothing wrong. It is self-defeating because they want to start new businesses, staff our labs, serve in our military, and otherwise contribute to the country we love. And it is cruel.