"Whether he intended to or not, what he communicated caused racists to rejoice, minorities to weep, and the vast heart of America to mourn," Romney wrote in a post on Facebook this morning.
"His apologists strain to explain that he didn't mean what we heard. But what we heard is now the reality, and unless it is addressed by the president as such, with unprecedented candor and strength, there may commence an unraveling of our national fabric," Romney said.
"Accordingly, the president must take remedial action in the extreme," he wrote.
Romney wrote that Trump should "address the American people, acknowledge that he was wrong, apologize."
"State forcefully and unequivocally that racists are 100% to blame for the murder and violence in Charlottesville. Testify that there is no conceivable comparison or moral equivalency between the Nazis -- who brutally murdered millions of Jews and who hundreds of thousands of Americans gave their lives to defeat -- and the counter-protestors who were outraged to see fools parading the Nazi flag, Nazi armband and Nazi salute," Romney wrote.
"Mr. President, act now for the good of the country," he concluded.
This latest public rebuke stands in stark contrast to better times in the Romney-Trump relationship. Trump endorsed Romney in 2012, but then when it was Trump's turn to run 2016, Romney became one of Trump's most vocal critics, and at one point held a press conference urging delegates in upcoming primaries to do whatever they could to prevent Trump from becoming the party's nominee.
They appeared to reach a truce after Trump won, and Romney was very publicly considered to fill the role of Trump's secretary of state, but then was not chosen.