Ted Cruz calls Donald Trump a 'snivelling coward'

Ted Cruz has called Donald Trump a "snivelling coward" in the latest exchange of nasty blows between the two Republican presidential candidates.

"It's not easy to tick me off, I don't get angry often...but you mess with my wife, you mess with my kids, that will do it every time," he told reporters at a campaign event.

"Donald, you're a snivelling coward and leave Heidi the hell alone."