About 68 billion won ($58.4 million) out of South Korea's defense contributions to the United States Forces Korea (USFK) over the six years from 2014 has been left unused, data from the defense ministry showed Monday.

According to the data released by Rep. Jeon Hae-cheol of the ruling Democratic Party, USFK has not used 67.88 billion won out of Seoul's contributions made since 2014 toward shared defense costs.

The amount of Korean defense contributions unused by the US reached 14.5 billion won in 2017, 20.4 billion won in 2018 and 7.9 billion won in 2019, the data found.

Jeon, who belongs to the National Assembly Foreign Affairs and Unification Committee, released the defense data amid the two countries' long-stalled discussions on defense cost-sharing.

Jeon and other Korean politicians said that such a huge amount of unused defense costs should be fully reflected in the upcoming defense cost-sharing negotiations, noting USFK has failed to transparently disclose how it has handled the unused money.

They said almost all of the personnel expenses out of Korea's defense contributions have been used, but it is believed that USFK has not spent a large amount of the budget earmarked for military facility improvements every year.

The military facility improvement sector accounted for 5.9 billion won, or 75 percent, of last year's unused defense contributions from Seoul.

"The annual recurrence of unused money out of South Korea's defense contributions indicates there could have been some structural problems in bilateral defense-cost sharing talks," said Jeon, calling for efforts to terminate the practice. (Yonhap)