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AUSTIN (AP) — All 20 Texas Senate Republicans sent a letter Monday to President Barack Obama demanding more flexibility for their state to administer Medicaid — but also vowing that, without it, expanding the program under the White House’s signature health care law remains “not worth discussing.”

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Sen. Charles Schwertner said the cost of covering the joint federal-state program providing health care for the poor and disabled has grown from 12 percent of Texas’ state budget in 1989 to nearly 30 percent today, saying it’s increasing two and a half times faster than any other part of state government.

The letter said such a trajectory “is clearly unsustainable.”

Speaking at a state Capitol news conference with Lt. Gov. Dan Patrick, Schwertner likened federal reimbursements distributed as part of Medicaid “gold-plated handcuffs that stand in the way of common-sense, conservative reforms that could otherwise help contain these exploding costs.”

Texas wants to be allowed to collect co-payments and institute work requirements for recipients, as well as expand health saving accounts. Those ideas were panned by advocacy groups, which noted that Medicaid costs have increased because Texas successfully covered more previously uninsured children — and that they also have remained relatively stable since 2012.

“Low-income children, pregnant women, the elderly, and Texans with disabilities don’t need more hoops to jump through,” a coalition known as “Cover Texas Now” said in a joint statement.

Schwertner himself noted that getting Washington to agree to such overhauls was likely a tall order.

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“The federal government has been very unwilling to work with increased flexibility,” said the Georgetown Republican, who heads the Senate Health and Human Services Committee.

Texas’ demands come as the White House says the state would be eligible for up to $10 billion in annual subsidies if it expanded Medicaid to eligible Texans under the federal health care law. The idea, though, has been strongly opposed by the Texas Legislature.

“Until we receive the kind of federal flexibility we’re calling for here today, the kind needed to fundamentally reform Texas’ existing Medicaid program in a way that preserves it for our most-vulnerable Texans,” Schwertner said “any expansion of Medicaid in Texas is simply not worth discussing.”

Tea party favorite Patrick went further, saying the letter to the president helped mark Texas Independence Day on Monday because it was time for “independence from overreaching federal mandates like Obamacare.”

Texas, meanwhile, is in the process of renegotiating with the U.S. Centers for Medicare and Medicaid Services an existing five-year, nearly $30 billion Medicaid waiver mostly used to reimburse hospitals for uninsured care and set to expire in September 2016.

Schwertner said Monday’s demands wouldn’t hinder those negotiations, though, and the Centers for Medicare and Medicaid Services has long maintained it’s willing to work to increase flexibility for individual states.

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