Story highlights Obama slams Trump's outlandish statements

You have to do your homework, Obama warns

Vientiane, Laos (CNN) President Barack Obama warned Thursday against becoming immune to Donald Trump's more outlandish statements, arguing that the stakes of the US presidential contest were too high for Americans to tune out.

"People start thinking behavior that in normal times we would consider completely unacceptable and outrageous becomes normalized," Obama said during a news conference at the tail end of his visit to Laos.

"People start thinking that we should be grading on a curve," he said. "But I can tell you from the interactions I have had over the last eight or nine days with foreign leaders that this is serious business."

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Obama has repeatedly warned against the perils of the Trump presidency, suggesting the Republican nominee would be woefully unprepared to take office should he win in November.

When he's abroad, Obama has relayed fears from foreign leaders, who he says question him often about the state of the US presidential contest.

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