US Secretary of Defense Mark Esper and his South Korean counterpart Jeong Kyeong-doo Photo: IC

US Secretary of Defense Mark Esper pressed South Korea on Friday to pay more for the cost of stationing US troops in the country and to maintain an intelligence-sharing pact with Japan that Seoul is about to let lapse.

Speaking after a high-level defense policy meeting with his South Korean counterpart Jeong Kyeong-doo, Esper also said the two countries have to be flexible with their joint military drills. But he stopped short of announcing any changes to exercises next month that North Korea has sharply condemned.

The United States and South Korea are scrambling to clinch an agreement in the coming weeks to cover next year's costs of maintaining the 28,500-strong US military presence.

South Korea, Esper said, "is a wealthy country and could and should pay more" for the deployment of US military in the South.

"It is crucial that we conclude the (defense pact) ... with increased burden sharing by the Republic of Korea before the end of the year," Esper said.

Jeong said he and Esper shared the view that the cost-sharing pact should be fair and mutually agreeable, but it was unclear if they shared any sense of what a fair amount might be. 

A South Korean lawmaker said last week that US officials demanded up to $5 billion a year, more than five times what Seoul agreed to pay this year under a one-year deal.

Jeong said he and Esper also discussed personal views on South Korea's decision to end an intelligence-sharing pact with Japan, called GSOMIA, and that both governments will put in realistic effort to narrow differences before the pact expires on November 23.

Relations between the two neighbors have plunged after South Korea's top court last year ordered Japanese firms to compensate some wartime forced laborers, and Japan curbed exports of key industrial materials to South Korea in July.