Presidential hopeful Pete Buttigieg has criticized a Trump administration rule that will allow adoption agencies to refuse placement with LGBT couples.

The new Health and Human Services (HHS) rule undoes an Obama-era policy prohibiting discrimination on the basis of sexual orientation and gender identity among federal grantees, which include adoption agencies.

Speaking to the Washington Blade on his Iowa campaign bus, Buttigieg, the openly gay mayor of South Bend, Indiana, described the rule change as “a huge step backward.

“I think it's a huge step backward,” Buttigieg said on his way to a rally in Waverly, Iowa.

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“It's bad enough that discrimination is taking place across the country, but when discrimination is being supported with federal funds, it takes away, first of all the movement [toward] justice and equality, but also an opportunity for the federal government to show leadership in advancing equality.”

“This is different from telling religious organizations what their theology ought to be, or invading their practice or religious belief. We're talking about social services being offered in partnership with the taxpayer, and that creates an obligation and shared expectation for the United States,” he said.

Buttigieg added that under his leadership the rule would be revised in the direction of how it was implemented during the Obama administration.