The U.S. and the Republic of Korea (ROK) have failed to agree on a bigger ROK share of the cost of maintaining U.S. troops, an official said on Friday. 

U.S. President Donald Trump has repeatedly said that the ROK should bear more of the burden for keeping some 28,500 U.S. troops in the ROK, where the U.S. has stationed forces since the Korean War. 

Senior officials from both sides held three-day talks in Seoul from Tuesday to hammer out an accord to replace a 2014 deal due to expire this year, which requires the ROK to pay about 960 billion won, about 850 million U.S. dollars this year. But after 10 rounds of negotiations, the two sides did not manage to come up with an agreement. 

The U.S. initially pushed the ROK to increase its share of the burden to about 1.2 billion U.S. dollars, The Wall Street Journal reported last week, citing unidentified sources.

"We've come to an agreement on almost all elements but could not make it final because of differences on the total scale of the deal," a senior ROK foreign ministry official told reporters on condition of anonymity. 

The ROK official said the two sides were not expected to meet again this year, raising the risk of a funding gap.

(Top image: The welcome ceremony for General Robert Abrams who assumed command of U.S. forces in the ROK, November 13, 2018 /VCG Photo)