Former President Barack Obama told college graduates that the "folks in charge" don't always know what they're doing in rare public criticism of the Trump administration on Saturday.

Obama criticized the handling of the coronavirus pandemic without mentioning President Donald Trump by name, just a week after privately critiquing the administration's response to the Covid-19 crisis.

"This pandemic has fully, finally torn back the curtain on the idea that so many of the folks in charge know what they're doing. A lot of them aren't even pretending to be in charge," the 44th President said during a virtual commencement address for historically black colleges and universities.

"If the world is going to get better, it's going to be up to you," he added.

White House press secretary Kayleigh McEnany on Saturday touted Trump's work, saying in a statement to CNN that "President Trump's unprecedented coronavirus response has saved lives."

Obama then later Saturday night, during the "Graduate Together" special hosted by LeBron James, said, "You know, all those adults that you used to think were in charge and knew what they were doing, turns out they don't have all the answers. A lot of them aren't even asking the right questions."

CNN previously reported that Obama had privately criticized the Trump administration's response to the coronavirus crisis as "an absolute chaotic disaster" during a phone call earlier this month with former staffers and administration alums.

The impact of coronavirus on communities of colour

During his message to the HBCU graduates, Obama also spoke of how the pandemic has disproportionately affected black communities.

"A disease like this just spotlights the underlying inequalities and extra burdens that black communities have historically had to deal with in this country. We see it in the disproportionate impact of Covid-19 on our communities," he said during the "Show Me Your Walk" virtual commencement program.

"Just as we see it when a black man goes for a jog and some folks feel like they can stop and question and shoot him if he doesn't submit to their questioning. Injustice like this isn't new," Obama said, referring to the killing of Ahmaud Arbery, a young black man in Georgia.

Obama, who was a former civil rights lawyer and community organizer before he ran for political office, also gave three pieces of advice for the graduating class to "create change."

"No generation has been better positioned to be warriors for justice and remake the world," Obama said.

He encouraged the HBCU graduates to organize at the grassroots level (and not just resort to online activism), to grow allies in the fight for a common cause, and remember "you're all role models now, whether you like it or not."

"Your participation in this democracy, your courage to stand up for what's right, your willingness to forge coalitions, these actions will speak volumes," he said. "And if you're inactive, that will also speak volumes."

Three pieces of advice to the class of 2020

The former President, in the second virtual graduation ceremony, gave out three pieces of advice to this year's students: don't be afraid, do what you think is right, and build a community.

"America's gone through tough times before ... and each time we came out stronger, usually because of a new generation, young people like you, learned from past mistakes and figured out how to make things better," he said.

Speaking about doing what you think is right, Obama said in part, "I hope that ... you decide to ground yourself in values that last, like honesty, hard work, responsibility, fairness, generosity, respect for others. You won't get it right every time, you'll make mistakes like we all do. But if you listen to the truth that's inside yourself, even when it's hard, even when it's inconvenient, people will notice. They'll gravitate towards you. And you'll be part of the solution instead of part of the problem."

Lastly, on building a community, the former President said, "No one does big things by themselves. ... if we're going to save the environment and defeat future pandemics, then we're going to have to do it together.

"Stand up for one another's rights. Leave behind all the old ways of thinking that divide us -- sexism, racial prejudice, status, greed -- and set the world on a different path," he added.

Obama closed out his remarks with, "Congratulations, Class of 2020. Keep making us proud."