AUSTIN (AP) – House and Senate negotiators on Thursday approved a $172 billion Texas budget for the next two years, sending it to the full chambers for a weekend vote.

Budget leaders expect House and Senate votes on Saturday, which would then send the massive document to the governor before the session is scheduled to end Monday.

Money for schools, however, remains in limbo.

The plan makes $37 billion for basic school operations contingent on lawmakers agreeing to a new distribution system before the session adjourns Monday.

Agreement on new school funding formulas has been an obstacle so far. A lack of an agreement on how to distribute the school money by Monday would almost certainly require lawmakers to return to Austin for a special session over the summer.

“If there is no agreement between the House and Senate on school finance, then the fact that there’s no appropriation for the Foundation School Program, we’d have to come back for a special session,” said Sen. Steve Ogden, the Senate’s chief budget writer.

Rep. Jim Pitts, the lead budget writer for the House, said negotiators were working long hours to reach a school-funding agreement.

Lawmakers have been grappling with a multibillion-dollar revenue shortfall since January. Republican leaders have vowed not to raise taxes and want to limit how much they spend from the state’s Rainy Day Fund. The reserve fund is projected to have a balance of almost $10 billion, before a $3.1 billion withdrawal for a current-year deficit.

Instead, they’ve made massive cuts to all levels of state government, including public schools and health care for the disabled, elderly and poor.

“If the Legislature adopts this budget, the Legislature will have failed to meet the needs of Texas,” said F. Scott McCown, executive director of the Center for Public Policy Priorities, which advocates for the needy.

“The far right’s demand that our state’s revenue crisis be addressed by cuts alone instead of through a balanced approach that uses the Rainy Day Fund and adds new revenue has forced damaging cuts to essential state services.”

Overall, the budget makes $15 billion in cuts compared to current spending. That doesn’t account for billions in expected costs related to population and enrollment growth.

“Under the circumstances, this is a great budget and it does adequately fund state services,” Ogden said. “It’s not without pain and … budgets are going to be tight, but Texas will be fine under this budget for the next two years, in my opinion.”

Even though the budget conference committee agreed to spend more on public education, school operations still would be underfunded by about $4 billion under current law.

Spending on Medicaid, also, would not pay for more than $4 billion expected to be needed for projected enrollment growth.

Ogden called the finished document an “extraordinary accomplishment” given the circumstances.

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