"It is disqualifying for a modern-day presidential nominee to refuse to release tax returns to the voters," Romney said in a Facebook post about Trump, who became the likely Republican nominee when his rivals dropped out last week.
"There is only one logical explanation for Mr. Trump's refusal to release his returns: there is a bombshell in them," Romney said. "Given Mr. Trump's equanimity with other flaws in his history, we can only assume it's a bombshell of unusual size."
Trump has said that he will make public his tax returns on the completion of an audit.
Banner and thumbnail credit: Reuters, Jim Urquhart