South Koreans hired by U.S. troops here will be forced to take unpaid leave if a renewed defense-cost sharing pact fails to win early approval from Seoul‘s parliament, the foreign ministry said Thursday.

After months of tough negotiations, Seoul and Washington renewed in January their Special Measure Agreement on jointly burdening the costs of stationing United States Forces Korea in South Korea.

Under the new contract covering the five-year period from 2014, South Korea is to pay 920 billion won (US$863 million) to USFK this year. The new pact requires parliamentary approval before going into force, but the chance of early approval looks slim amid strong protests from opposition lawmakers.

“The USFK side has told us several times that they will have to send South Korean workers (employed by USFK) on unpaid vacation from April 1 if the defense-costs sharing pact does not go into effect (before the deadline),” foreign ministry spokesman Cho Tai-young said.

“The government strongly desires early ratification from the National Assembly.”

Given the limited amount of USFK funds earmarked for the labor costs for the South Korean workers, the U.S. side could not afford to keep the local workforce without the injection of more finances through the new SMA pact, Cho said.

Local military-supply companies that used to take business orders from USFK may also suffer a lack of enough orders due to the feared delay in winning early parliament approval, the spokesman also noted.

“(The possible delay is) feared to force South Korean workers to take unpaid leave as well as weakening of USFK’s combat readiness,” Cho also noted.

The new pact has been pending in parliament since early February.

Opposition lawmakers and civic groups, however, have boycotted the new Seoul-Washington pact, criticizing a sharp rise in South Korea‘s share. The 2014 annual contribution required for South Korea under the new pact marks a 5.8 percent hike from what the country paid last year under the expired agreement over the last five years.

They have also demanded more transparency in the ways that USFK uses and deposits South Korean-contributed funds.

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.

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