Rivals trash Trump's migrant plan

Donald Trump reiterated his pledge during Tuesday's Republican presidential debate to deport millions of undocumented workers, a plan trashed by rivals including Jeb Bush, who warned overzealous anti-immigrant sentiment would be a gift to Democrats.

"We will have a wall. The wall will be built. The wall will be successful," Trump, the Republican frontrunner and real estate tycoon, said about the partition he has vowed to build on the southern US border with Mexico.

Asked directly by a moderator if he would deport five million immigrants, Trump said, "You will have to send people out."

But he refused to explain what impact he thought such mass deportations would have on the US economy.

"We're a country of laws. We either have a country or we don't have a country," he said.

The issue surfaced in the party's fourth debate of the 2016 primary cycle one day after a federal appeals court blocked measures announced by President Barack Obama last year that would give work permits and deportation protection to more than four million undocumented migrants.

Bush stepped in to warn that sending back half a million immigrants per month "is just not possible."