President Obama Offers Debate Advice for Hillary Clinton: 'Be Yourself'

— -- In an exclusive interview with ABC News' "Good Morning America," President Obama offered his advice for Hillary Clinton as she prepares to debate Donald Trump for the first time.

"Be yourself and explain what motivates you," the president told "GMA" co-anchor Robin Roberts today in an exclusive interview at the Smithsonian National Museum of African American History and Culture. "I've gotten to know Hillary and seen her work and seen her in tough times and in good times. She is in this for the right reasons. She is motivated by a deep desire to make things better for people."

Tune into "Good Morning America" on Friday for more of Robin Roberts' exclusive interview with President Obama and First Lady Michelle Obama.

The president encouraged Clinton, whom he said will be an "outstanding president," to use the debate as a venue to not only talk about policy, but also what has inspired her to carry on in the face of adversity.

"I think there is a reason we haven't had a woman president before and so she is having to break down some barriers," he said. "There is a level of mistrust and a caricature of her that doesn't jibe with who I know, this person that cares deeply about kids, and wants to make sure they get a good education and wants to make working families have support and wants everyone to succeed and wants to keep America safe."

"To the degree to which she can talk not just about policy, but talk about why she has been able to despite all the slings and arrows that have been cast at her, just keep on going," the president added. "It would be good for the American people to see that and be reminded of that."

Clinton and Trump will face off in their first of three presidential debates on Monday at Hofstra University on Long Island, New York.