Leading Republican Romney says Trump not fit for presidency

Republican 2012 White House nominee Mitt Romney excoriated Donald Trump as unfit to be president Thursday, in a deeply personal attack that exposed party panic at the billionaire's political success.

Baldly stating that "Donald Trump is a phony, a fraud," Romney said his party's frontrunner "has neither the temperament nor the judgment to be president."

Romney offered a litany of pejorative descriptions of Trump, saying he was greedy, dishonest, bullying and misogynistic.

His stem-winder is highly unusual in a party that long swore by Ronald Reagan's "11th commandment" "Thou shalt not speak ill of any fellow Republican."

But Trump's shock electoral success has provoked utter panic among the Republican establishment, who believe he will destroy the party if he wins the nomination.

Warning of "profound consequences for the Republican Party," Romney said that "if we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished."

It is far from clear that Romney's intervention will stop Trump's meteoric rise.

The real estate mogul has defied expectations in winning nine of the 15 state-wide primary contests held so far, garnering more than three million votes.

Using seemingly unlimited free media coverage, Trump has tapped into deeply felt grassroots anger at the party leadership.

Romney was quick to scotch suggestions he may use the speech to back a rival or throw his hat into the ring.

"I am not here to announce my candidacy for office," he said. "I am not going to endorse a candidate today."

Romney heavily lost the 2012 election to incumbent president Barack Obama.

Diplomatically, he listed Ted Cruz, Marco Rubio, and John Kasich and said "one of these men should be our nominee."