Housing and Urban Development Secretary Ben Carson proposed change to federal subsidies that would triple the rent for millions of low-income tenants in government housing and impose work requirements.

On Wednesday, Carson uncovered the plan that would increase rent to 35 percent of the gross income for over 2 million families. Currently, families pay 30 percent of adjusted income for housing, The Washington Post reports.

More than 700,000 of the poorest households could see their rental caps increase to $150 from the current $50, per HuffPost.

“Every year, it takes more money, millions of dollars more, to serve the same number of households,” Carson said on a call with reporters. “It’s clear from a budget perspective and a human point of view that the current system is unsustainable.”

Carson’s plan also would give public housing authorities the power to require minimum work requirements. Currently, 15 out of the nation’s 3,100 housing agencies require people to work to be eligible for benefits, according to The WashingtonPost.

The elderly and the disabled would be excluded from the rent increases and work requirements, per reports.

Housing advocates blasted Carson’s proposal, calling it “cruel.”

“When we are in the middle of a housing crisis that’s having the most negative impact on the lowest-income people, we shouldn’t even be considering proposals to increase their rent burdens,” Diane Yentel, president of the National Low Income Housing Coalition, told the Post.

The proposal comes in line with the Trump administration’s push to restrict federal assistance.