Updated

Republicans are moving to block the Obama administration from "unilaterally weakening" welfare rules, after the Department of Health and Human Services last week quietly notified states they may seek a waiver from the program's work requirements.

House and Senate Republicans introduced a bill Wednesday to prohibit the administration from implementing its latest policy or approving any change that "waives compliance" with the program's work rules.

They claimed the administration had "overstepped its bounds" while "eviscerating" planks from the 1996 bipartisan agreement on welfare reform.

"Gutting welfare work requirements with the stroke of a pen and without congressional input is simply unacceptable and cannot be allowed to stand," Sen. Orrin Hatch, R-Utah, said in a statement. "Neither the Obama administration nor any administration should have the power to unilaterally change the law as it sees fit."

The Department of Health and Human Services, though, is defending the change, claiming it was in response to states burdened by current rules and guidelines.

More On This...

HHS Secretary Kathleen Sebelius says the waivers won't get in the way of moving welfare recipients into jobs. She sent letters late Tuesday to Republican lawmakers who oppose the waiver plan, saying states will have to promise to move at least 20 percent more people from welfare to work and show "clear progress" within a year. Sebelius said GOP governors have long sought more flexibility from the administration.

In last week's policy directive, the department said states may seek a waiver from the work component of the Temporary Assistance for Needy Families Program, in order to "test alternative and innovative strategies, policies and procedures that are designed to improve employment outcomes for needy families."

HHS stressed that any alternative should still aim to get welfare recipients into gainful employment. Any plan that "appears substantially likely to reduce access to assistance or employment for needy families," will not be approved, the memo said.

George Sheldon, acting assistant secretary for the Administration for Children and Families, said in a blog last week that states will be held "accountable" for their alternative plans.

"The new steps we have taken will give states more flexibility in how they operate the Temporary Assistance to Need Families program. And the steps we have taken were specifically requested by states led by officials from both parties," he wrote.

The hard-fought welfare reform agreement in 1996 was struck between the Bill Clinton administration and a Republican-led Congress. It is still considered a signature legislative achievement from that period.

The Associated Press contributed to this report.