South Korean rescue members wearing chemical protective suits take part in an anti-terror drill at a subway station in Seoul on Tuesday, on the sidelines of a South Korea-US joint military exercise. Tens of thousands of South Korean and US troops are taking part in the "Ulchi Freedom Guardian" joint military drills, a largely computer-simulated exercise that runs for two weeks. Photo: AFP

South Korea has agreed to a 13.9 percent increase in its contribution to the cost of hosting some 28,500 US troops for 2021, the biggest annual rise in nearly two decades, its foreign ministry said on Wednesday.

The increase will take South Korea's contribution in 2021 to 1.18 trillion won ($1.03 billion). Former US President Donald Trump questioned the extent of US funding of the defense of allies and had demanded that South Korea pay as much as $5 billion a year.

"The agreement resolved a vacuum that had lasted about a year and three months," the foreign ministry said. "It provided a chance to reaffirm the importance of the alliance and the need for stable stationing of US Forces Korea."

The six-year Special Measures Agreement with the US, which came after drawn-out negotiations and will boost South Korea's annual contribution to the bill from 2022 to 2025 in line with its annual defense budget increase, which was 5.4 percent in 2021, the foreign ministry said.

The pact replaces an arrangement that expired at the end of 2019, under which South Korea paid about $920 million a year. 

In the last big annual increase, in 2003, South Korea paid 17 percent more than the previous year, according to data from a defense ministry white paper.

On the new link between the contribution to the cost of maintaining US forces and the defense budget, the ministry said the increase in the defense budget was a "reasonable, clearly verifiable standard" that reflected financial and security capabilities.

AFP