U.S. Secretary of State John Kerry expressed optimism Tuesday that Seoul and Washington will soon reach a deal on rewriting a pact on the two nations' civilian nuclear cooperation.
Revising the agreement, signed in 1974, is one of the most urgent and thorniest bilateral issues, as the existing one expires in March next year.
Seoul is hoping for Washington's consent to enriching uranium and reprocessing spent fuel, a move opposed by U.S. officials dealing with nonproliferation issues.
After talks with his South Korean counterpart, Yun Byung-se, Kerry said he was "very hopeful" that the problem will be resolved before South Korean President Park Geun-hye's trip here in early May.
"I'm very hopeful -- and I think the foreign minister shares this hope _ that this can be resolved before the visit of President Park," Kerry said at a joint press conference in the Benjamin Franklin Room on the eight floor of the State Department building.
It was their first meeting since they became the top diplomats of the allies earlier this year. Both Kerry and Yun said they had "good discussions" on the matter, which has drawn keen public attention in South Korea alongside the North Korea crisis.
Under the current pact, South Korea is prohibited from enriching uranium, resorting to importing it from the U.S., and reprocessing spent fuel.
South Korean officials argue Seoul needs a more stable source of nuclear fuel as the country's nuclear industry has grown to become one of the world's largest and best.
South Korea has about two dozen nuclear reactors to produce 36 percent of its total energy need. Its nuclear waste storage facilities are also expected to reach capacity in 2016.
"We have a long record of close cooperation on this issue, and we are committed to finding a workable, expeditious way forward," Kerry said.
He said decades-long nuclear energy partnerships between the two sides will "continue in an agreed-upon fashion."
He said he and Yun will have follow-up discussions on the matter when he travels to Seoul next week. The South Korean minister said he stressed to Kerry the importance of revising the agreement "in a mutually beneficial, timely and forward-looking manner."
"Both sides will continue consultations in this regard," Yun said. A diplomatic source noted the high-level commitments by Kerry and Yun to handling the sensitive issue in a quick and smooth way.
The source, however, said it does not necessarily mean Seoul and Washington have narrowed their differences. "The U.S. continues to ask South Korea to lower its bar, while South Korea shows no sign of backing down in its demands," the source said.