Romney vs Trump
- Romney says Republicans must look beyond this election to find its future
- Former presidential nominee says he will not vote for Trump in election
- Trump says Romney "choked like a dog" when he lost in 2012 election
- Spat comes amid controversy in Republican party over presumptive nominee
Mitt Romney, the former Republican presidential candidate, has condemned Donald Trump for setting a dangerous example for Americans by promoting "trickle-down racism".
Speaking in Utah at his annual business and politics summit on Saturday, Romney said the Republican party must look beyond this presidential election to find its future.
Firing back, Trump went on Twitter to note how Romney "choked like a dog" when he lost to then-incumbent President Barack Obama in 2012 and repeated it at his campaign stops.
Some other senior Republicans have also criticised Trump in recent weeks for attacking US District Judge Gonzalo Curiel, a Mexican-American judge presiding over a case against him.
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"Presidents have an impact on the nature of our nation, and trickle-down racism, trickle-down bigotry and trickle-down misogyny - all these things are extraordinarily dangerous to the heart and character of America," Romney said in Utah.
He said he expected Trump to get the Republican nomination, but added that he would not vote for either Trump or Clinton.
Romney left open the possibility of casting a ballot for the Libertarian Party candidate, Gary Johnson, a former New Mexico governor.
On Tuesday Paul Ryan, the top elected US Republican and Speaker of the House of Representatives, criticised Trump's remarks on the judge for what he called a "textbook definition of a racist comment".
Unlike Romney, Ryan has endorsed Trump as the Republican nominee.
Ohio Governor John Kasich, who was a nominee for Republican candidacy earlier in the year, said on Thursday that he still was not ready to endorse Trump.
"Why would I feel compelled to support someone whose positions I kind of fundamentally disagree with?" he told Fox News.
As the presumptive nominee, Trump now has to balance maintaining the outsider style that helped propel him to the nomination, while courting Republican insiders, who could be critical to financing a general election campaign against a well-funded Clinton.
On Friday, at a Christian evangelical conference, Trump offered a message of ethnic harmony as he sought to calm concerns about his criticism of the Mexican-American judge.
In a departure from his usual freewheeling style, Trump read a carefully scripted speech from a teleprompter as part of a new push by his campaign to tone down his harsh rhetoric.
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Trump did not mention the controversy over his charge that Curiel is unable to treat him fairly because of his Mexican heritage.
Trump also said he would represent all Americans if elected president on November 8.
"Freedom of any kind means no one should be judged by their race or their colour and the tone of his hue," Trump said.
Source: Al Jazeera and agencies