With Trump seizing the mantle of presumptive Republican nominee this week after his rivals exited the race, debate has turned to whether he will be able to rally the party faithful behind him between now and November.
Asked on Friday night about Trump's candidacy and the resulting chaos on the Republican side, Obama offered some of his most pointed comments yet about the celebrity real estate mogul and longtime star of the TV show "The Apprentice," whose political rise has stunned the world.
"We are in serious times and this is a really serious job," Obama told reporters at the White House. "This is not entertainment. This is not a reality show."
"Every candidate, every nominee needs to be subject to exacting standards and genuine scrutiny."
Trump has raised howls of protest within his own party with his harsh, free-wheeling speech and proposals ranging from banning Muslims from entering the United States to building a wall on the southern border to keep out Mexican migrants to slashing US funding for NATO so allies pay more.
"He has a long record that needs to be examined, and I think it's important for us to take seriously the statements he's made in the past," Obama said, Reuters reported.
US Secretary of State John Kerry piled on, telling a diverse and international graduating class at Northeastern University that they were "Donald Trump's worst nightmare."
"We will never come out on top if we accept advice from soundbite salesmen and carnival barkers who pretend the most powerful country on Earth can remain great by looking inward and hiding behind walls," he said.