About half a million children could lose their eligibility for free school lunches under a Trump administration proposal. 

Children whose families qualify for food stamps through the Supplemental Nutrition Assistance Program, known as SNAP, can automatically get free breakfasts and lunches at school, but the Trump administration's proposal would tighten eligibility for SNAP.

The U.S. Department of Agriculture released an analysis this week showing that nearly 3 million people could lose access to food stamps under the proposed rule, including almost 1 million children.

According to the analysis, children whose families lost SNAP benefits would have to submit an application to determine if they qualify for free or reduced-priced school meals. About 45% of them — some 445,000 kids — would still qualify for free meals. But most of the others — about 497,000 kids who currently get free meals — would have to start paying a reduced price of 40 cents for school lunch and 30 cents for breakfast, since they come from families with an annual income of between 130% and 185% of the federal poverty level.

Another 40,000 kids who currently get free meals would need to pay the full price because their family won't qualify for the program anymore. 

According to the USDA, the proposal could cut $90 million annually from the cost of its school lunch and breakfast programs. The agency noted that the number of children being affected by the proposal could be less because some schools offer free lunches to all students regardless of eligibility. 

Agriculture Secretary Sonny Perdue has said tightening access to SNAP would close a "loophole" that allows families receiving temporary assistance benefits to automatically get food stamps too.

But critics argue that the change will increase food insecurity among low-income families and add to states' administrative costs.