Trump: 'I could shoot somebody and not lose any voters'

Presidential hopeful Donald Trump has shown his supreme confidence in the loyalty of his supporters by proclaiming that they would stick by him even if he shot someone in a busy street.

The Republican frontrunner was speaking at a rally just nine days ahead of the Iowa caucuses - part of the selection process for the Republican party candidate.

Addressing the crowds, he said:

Last week, Trump received the "coveted" endorsement from former Republican vice-presidential candidate Sarah Palin who said Trump was "going rogue left and right" and would allow the military do its job and destroy the Islamic State group.

Separately, fellow billionaire and former New York mayor Michael Bloomberg has instructed advisers to make plans for an independent presidential run this year.

He is said to be troubled by Donald Trump's dominance of the Republican party and concerned at Hilary Clinton's struggles against Bernie Sanders for the Democrats.

US media reports say Bloomberg would be willing to spend up to $1 billion of his fortune on a campaign with a final decision expected by early March.