'That's nativism, or xenophobia, or worse': Obama unloads in an extended rant about Trump

President Barack Obama unloaded on Donald Trump in a lengthy rant during a Wednesday press conference in Canada, implying that Trump is not really a "populist" and is instead exploiting people for his own gain.

Without ever mentioning the presumptive Republican presidential nominee by name, Obama implicitly attacked Trump for using the populist label to mask his appeals to what he described as nativist and xenophobic sentiments within the US electorate.

Alluding to Trump, Obama criticized the candidate who "has never shown any regard for workers, has never fought on behalf of social-justice issues or making sure that poor kids are getting a decent shot at life, have healthcare."

Obama also accused him of working against "economic opportunity for workers and ordinary people."

"They don't suddenly become a populist because they say something controversial in order to win votes," Obama said. "That's not the measure of populism. That's nativism. Or xenophobia. Or worse. Or it's just cynicism."

Obama praised Vermont Sen. Bernie Sanders, who challenged Hillary Clinton for the Democratic presidential nomination, for dedicating his career to fighting for people. Obama said Sanders was an example of someone who "genuinely deserves" to be called a populist.

"There are people like Bernie Sanders who I think genuinely deserve the title," Obama said. "Because he has been in the vineyards fighting on behalf of these issues."

Obama cautioned voters against gravitating to an opportunistic candidate.

"I would just advise everybody to be careful about suddenly attributing to whoever pops up at a time of economic anxiety the label that they're a populist," Obama said. "Where have they been? Have they been on the front lines working on behalf of working people?"

He concluded: "I'm not prepared to concede the notion that some of the rhetoric that's been popping up is populist."

Obama is in Ottawa this week for the North American Leaders' Summit.