Film star Richard Gere has said it is "mind boggling" that American citizens are voting for Donald Trump.

Billionaire businessman Trump achieved a decisive victory on Super Tuesday in the US, coming closer to winning the presidential nomination for the Republican Party.

He won seven states in the biggest day in the primary campaign, building his lead in the delegate count that will determine the party's official nominee at the national convention in the summer.

Speaking at a VIP screening of his film Time Out Of Mind at the Curzon Mayfair in central London, Gere said: " You can't ignore him. This is a guy who may well be the Republican nominee.

"As a person I don't think he's that interesting.

"What is interesting is, why would so many people be willing to support him, knowing that he represents all these horrible things? That's mind-boggling."

Trump has sparked outrage with many of his policies, which include building a wall in an attempt to halt illegal immigration from Mexico, and a short-term ban on Muslim immigrants.

He has also pledged in a campaign advertisement to "bomb the hell out of ISIS".

But despite initial derision when Trump announced his candidacy, the Republican has struck a chord with his party's voters.

The American actor added: "I don't blame him for that, I blame us.

"We have something inside of us that is almost completely ignorant of emotional realities on this planet."