MILWAUKEE – The University of Wisconsin system is being forced to dip into a huge, controversial “slush fund” that was kept under wraps until it was discovered in 2013.

UW officials were upset last year when the state passed a budget that cut $250 million in aid to the university system over the next two years.

MORE NEWS: From Classroom to Consulate Chef: Culinary Student Lands Dream Job at U.S. Embassy in Paris

Gov. Scott Walker and Republican lawmakers imposed the cut partially because of the discovery of $1 billion-plus in financial reserves the university quietly stored away without public disclosure, until its existence was revealed by a state audit three years ago.

Now the university system will be forced to use some of that money to balance its budget over the next year.

The UW Board of Regents approved a $6.23 billion budget for 2016-17 on Thursday in a meeting at UW-Milwaukee. Spending will increase $37.4 million over the current year, despite the state budget cuts, according to the Milwaukee Journal Sentinel.

The spending increase will result in a budget deficit, but that will be covered by the use of $160 million from the controversial reserves. More than half of that amount, about $107 million, will come from leftover tuition dollars, according to the Journal Sentinel.

Student fees will also increase by an average of $59 per year across the university system, the newspaper reported.

Raising in-state student tuition was not an option for the Board of Regents, because Walker has protected student pocketbooks by freezing tuition rates for the fourth straight year. The tuition freeze was also the result of the disclosure of the so-called UW “slush fund.”

MORE NEWS: Know These Before Moving From Cyprus To The UK

The existence of the large university fund balance was revealed during state budget hearings in 2013. The resulting outcry prompted a UW spokesman to acknowledge that “we did not draw attention” to the reserve funds.

The final 2016-17 budget that was approved by the Board of Regents Thursday was passed without public scrutiny.

The Wisconsin State Journal reported that it had requested copies of budget proposals presented to the Board of Regents prior to their final vote. University officials ignored the legal request and said they would not disclose details of the budget proposal until shortly before the vote on Thursday.