The United States has renewed its pressure on South Korea to show "flexibility" in negotiations on sharing the cost of maintaining U.S. troops on the Korean Peninsula.

U.S. Deputy Assistant Secretary of State for Korea and Japan, Marc Knapper, made the call during a virtual forum hosted by the Center for Strategic and International Studies. 

Knapper said Washington has recently accepted Seoul's proposal to fund the labor costs of Korean workers of the U.S. Forces Korea amid the stalled defense cost-sharing negotiations. 

He said the development addressed the "human cost" of failing to renew the Special Measures Agreement, but also concerns troop readiness. 

Knapper said he believes the U.S. has been "very flexible" and is now urging the South Korean government to show some flexibility.