Washington (CNN) Former first lady Michelle Obama expressed concern Friday over the Trump administration's decision to scale back school meal nutritional requirements.

"You have to stop and think, 'Why don't you want our kids to have good food at school? What is wrong with you, and why is that a partisan issue?" Obama said at the annual summit of the Partnership for a Healthier America , a nonprofit that works with the private and public sectors to fight childhood obesity. "Why would that be political?"

Obama's comments come a little over a week after Agriculture Secretary Sonny Perdue signed a proclamation that relaxes standards for the upcoming school year in three key areas: whole grains, salt and milk.

Under the new proclamation, states will be able to grant exemptions to schools experiencing hardship in meeting the 100% whole-grain-rich standard. Schools will no longer need to hit the strictest target for lowering sodium in foods offered to students. And meal programs will be able to serve students 1% flavored milk instead of fat-free flavored milk.

The policy change loosens school meal standards Obama advocated as first lady through Let's Move! , her signature public health campaign aimed at combating childhood obesity.

Obama -- who did not mention President Donald Trump or first lady Melania Trump by name -- emphasized that it's important to make sure parents think about the importance of healthy school lunches.

"Moms, think about this," she said. "I don't care what state you live in. Take me out of the equation; like me, don't like me, but think about why someone is OK with your kids eating crap."

Obama said she will continue to fight for the cause.

"My commitment to these issues is real," she said. "I picked this issue because there was deep passion for it as a mother. ... I'm going to continue working on this."

Glad to be back at the #PHASummit. No one should play politics with our kids' health. We owe them. Let's make our voices heard. pic.twitter.com/g2ZDbwZk5u — Michelle Obama (@MichelleObama) May 12, 2017

She also tweeted about the event Friday.

"Glad to be back at the #PHASummit," she wrote. "No one should play politics with our kids' health. We owe them. Let's make our voices heard."