The South Korean Cabinet approved two exchanges of notes on Tuesday that are linked to a new defense cost-sharing pact with the United States.

Last month, the allies struck a deal to renew the Special Measures Agreement aimed at jointly footing the cost of stationing the 28,500 United States Forces Korea troops on the Korean soil.

Under the deal, South Korea agreed to pay 920 billion won ($867 million) this year for the upkeep of the U.S. troops, a 5.8 percent increase from a year earlier. The pact, to be valid over the next five years, was submitted to the National Assembly last month for approval.

Along with the pact, the two sides adopted two exchanges of notes: one on the system improvement to guarantee transparency in Washington's use of Seoul's payment, and the other on implementation principles of Seoul-funded construction.

"In accordance of law, the notes simply require the Cabinet approval and the president's endorsement. Though they exist under the frame of the cost-sharing pact, they are technically independent, which require a separate legal process," said a foreign ministry official.

"The Cabinet today approved them, and we are now waiting for the president's decision, which would take as long as two days in general," she said, adding that they will take effect along with the SMA pact.

According to the deal on the system improvement, the U.S. agreed to boost bilateral coordination and transparency in administrating the fund by adopting a set of measures such as providing Seoul with biennial reports on how the money was spent.

It is the first time that the Seoul government "achieved such comprehensive instrumental improvements" from the U.S., which would alleviate public outcry for the alleged misuse of the funds, according to officials here.

The Seoul-Washington defense treaty had initially put the burden of financing U.S. defense activities solely on the U.S. side. The allies signed their first SMA in 1991, and the deal has since been renewed intermittently.

Seoul's burden for maintaining U.S. troops here has been on the rise from 812.5 billion won in 2011, 836.1 billion won in 2012 and to 869 billion won last year.

The USFK forces are stationed in South Korea mainly as a deterrent against North Korea, a legacy of the 1950-53 Korean War. (Yonhap)