Pulitzer prize-winning historian Saul Friedlander, a world authority on the Holocaust, said Friday he would leave the United States if Donald Trump was elected president.

The 83-year-old Israeli-American writer, who escaped the Nazis by being hidden in a Catholic boarding school in France, described Trump as a "dangerous crazy".

He said the controversial Republican candidate could win November's election because of Hillary Clinton's "tendency to lie and to hide things".

"One cannot exclude Donald Trump winning even though he is a dangerous crazy," he told AFP.

"He says whatever comes into his mind."

Friedlander's magisterial two-volume history of Nazi Germany and the Jews charts Adolf Hitler's rise to power in a period where populism was rising across the world as it is today. ...