"He has a long record that needs to be examined," Obama said at a press conference on job growth. "I think it's important for us to take seriously the statements he's made in the past."
The President stressed the impact the general election would have on the United States, urging candidates and voters to take the contest seriously.
"I just want to emphasize the degree of which we are in serious times, and this is a really serious job. This is not entertainment. This is not a reality show. This is a contest for the presidency of the United States."
Obama hit Trump indirectly on the lack of detail in his policy plans, and urged the media and voters to vet candidates' policies.
"Every candidate, every nominee, needs to subject to exacting standards and genuine scrutiny," he said.
The President issued a warning to the media, emphasizing the impact their reporting could have on voters.
"What I'm concerned about is the degree to which reporting and information starts emphasizing the spectacle of the circus because that's not something we can afford," Obama said. "And the American people, they've got good judgment, they have good instincts, as long as they as have good information."
Hillary Clinton, while campaigning in California on Friday, echoed the President, telling an audience that journalists need to ask follow-up questions wehn the presumptive Republican nominee declines to give details.
"Donald Trump says he is going to repeal it," Clinton said of the Affordable Care Act. "Somebody should ask, 'What are you going to replace it with?' and if the answer is 'something great,' there should be at least a follow-up question, don't you think?"
Clinton told MSNBC earlier this week that pressing Trump for specifics on his policies will be a "big part of my campaign."
Obama wasn't the only member of his administration to discuss Trump on Friday.
Vice President Joe Biden warned against dismissing Trump's candidacy as a farce, telling a Pittsburgh television station that the presumptive GOP nominee could win over skeptical voters.
"We all make a mistake if we don't take (Trump) seriously," Biden told CNN affiliate KDKA.
Trump has the ability "to bring significant people around him on domestic and foreign policy and to do the policy pieces where people think that this guy could actually be president," Biden said. The vice president has previously lambasted Trump for his policies on immigration and refugees.
Secretary of State John Kerry also called out Trump on Friday in his commencement address at Northeastern University.
"You are the most diverse class in Northeastern's history -- in other words, you are Donald Trump's worst nightmare," Kerry said to applause.