SEOUL, March 10 (Xinhua) -- South Korea has agreed with the United States to increase its burden for the defense cost for the U.S. Forces Korea (USFK) by 13.9 percent, Seoul's foreign ministry said Wednesday.

The South Korean (L) and American flags fly next to each other at Yongin, South Korea, August 23, 2016. (Photo: Agencies)

The agreement on the 11th Special Measures Agreement (SMA), a South Korea-U.S. deal to share the upkeep cost for about 28,500 U.S. troops stationed in the Asian country, was reached after three-day negotiations last week in Washington.

Under the deal that will last until 2025, South Korea will pay 1.183 trillion won (1.04 billion U.S. dollars) in 2021, up 13.9 percent from 1.039 trillion won (910 million U.S. dollars) in 2020.

South Korea's 2020 payment was unchanged from the previous year as the Seoul-Washington negotiations were stalled under the previous U.S. administration. The 10th SMA expired at the end of 2019.

The 13.9 percent increase reflects a 7.4 percent growth in South Korea's defense budget in 2020 and a 6.5 percent expansion in payroll cost for South Korean employees in the USFK.

Since 1991, South Korea has shared the upkeep cost for the USFK, including cost for South Korean civilians hired by the USFK, construction of military installations and logistics support.