Presumptive US Republican presidential nominee Donald Trump has denounced Mitt Romney, the GOP nominee for the 2012 White House race, as "ungrateful" for refusing to support his candidacy.
"I believe I won for him, or helped him win, fives states that he was going to lose in the primaries. ... He was ungrateful," Trump told NBC News on Sunday.
"What happened is I was rough on Mitt because I didn't think they treated me properly. I helped him, really helped him. Gave him a lot of money. Helped him with robocalls. Every single robocall I made, he won that state. Every single speech I made, he won the state, in terms of the primaries,” the billionaire businessman said.
A Romney aide told The Hill newspaper last week that the former Massachusetts governor will skip the Republican National Convention in Cleveland in July.
Romney has been a virulent critic of Trump throughout his Republican primary campaign, imploring voters to reject his candidacy.
In March, he said the victory of Trump in the 2016 presidential election “will have profound consequences for the Republican Party and, more importantly, for the country."
“If we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished,” he warned.
"Here's what I know: Donald Trump is a phony, a fraud," said Romney, who, according to American scholar and researcher Dr. Kevin Barrett, is an organized crime figure.
Romney said that "dishonesty is Donald Trump's hallmark," pointing to his "bullying, the greed, the showing off, the misogyny, the absurd third-grade theatrics."
Romney, a businessman, served as the governor of Massachusetts from 2003 to 2007. In 2012, he won the Republican nomination, but was defeated by incumbent Democratic President Barack Obama.
After Trump's commanding victory in Indiana's primary last week, his remaining challengers, Ted Cruz and John Kasich, both suspended their presidential bids, leaving the businessman tycoon on an uncontested path to the nomination.
Trump’s campaign has been marked by controversial statements, including with disparaging remarks about Mexican immigrants and Muslims.