IMF said in a statement the program aims to "support the authorities' economic reform program"

The International Monetary Fund on Wednesday approved a $6 billion, three-year loan for Pakistan to try to right the South Asian nation's economy.

With the IMF board's approval, the fund released $1 billion to Pakistan immediately and said in a statement the program aims to "support the authorities' economic reform program" and to help "reduce economic vulnerabilities and generate sustainable and balanced growth."

The fund will review Pakistan's performance quarterly over 39 months, phasing release of the additional aid over time.

The government agreed on the loan program last month and announced plans to slash civil expenditures and freeze military spending while promising to substantially raise revenues to stem a yawning fiscal deficit, and pledging to collect 5.5 trillion rupees ($36 billion) in taxes.

Discontent is simmering in the country following repeated devaluations of the rupee, soaring inflation, and increasing utility costs, while tax collection has been a long-standing challenge for authorities.

"Pakistan is facing a challenging economic environment, with lackluster growth, elevated inflation, high indebtedness and a weak external position," the result of a "legacy" of uneven policies, IMF mission chief Ernesto Ramirez Rigo said in a statement in June.

The agreement includes a primary budget deficit target of 0.6 percent of GDP -- excluding debt service costs.