The delay means the U.S. will continue to command American and South Korean forces on the peninsula in wartime instead of ceding control to South Korea at the end of next year as had been planned. Yonhap News reported the move was made at South Korea’s urging.

The U.S. has held wartime command of South Korean troops since the 1950-1953 Korean War that ended in a truce without a peace treaty. The new agreement marks the second time that a transfer of control has been delayed, reflecting concern about North Korea’s nuclear missile program and doubts about the adequacy of South Korea’s defenses.

“While this agreement will delay the scheduled transfer of operational control, it will ensure that when the transfer does occur, Korean forces have the necessary defensive capabilities to address an intensifying North Korean threat,” Hagel said at a joint press conference at the Pentagon with South Korea’s defense minister, Han Min Koo.

South Korea has set a goal of mid-2020 for building up enough military capability to ensure a smooth transfer of control, Han said. “The security situation on the Korean peninsula is more precarious than ever,” the minister said through an interpreter.

North Korea has significantly improved its nuclear and missile technology in recent years, Defense Ministry spokesman Wi Yong Seob told reporters in Seoul today.

‘Conditions-Based’

Any future transfer of wartime control would be “conditions-based” in hopes of “strengthening a combined defense force led by the Republic of Korea,” Han said.

American officials have said an improved missile-defense system for South Korea would be a prerequisite for handing over command.

South Korea has been reviewing its missile-defense options, including whether to buy Lockheed Martin Corp. (LMT:US)’s Terminal High-Altitude Area Defense system, known as THAAD.

South Korea has said it will buy 40 F-35A fighters made by Bethesda, Maryland-based Lockheed.

The U.S. has stationed about 28,500 troops in South Korea since an April 2008 agreement between President George W. Bush administration and the South Korean government. The number had been closer to 35,000 for years before that accord.

Seo Bok Kyung, a researcher at the Sogang University Institute of Political Studies in Seoul, said the government made the decision without consulting lawmakers.

“What the government did this time was not part of the democratic process,” Seo said. “The government should have enhanced publicity on this issue even if there was a serious threat to the national security or war threats due to collapse of the North Korean regime.”

To contact the reporter on this story: David Lerman in Washington at dlerman1@bloomberg.net

To contact the editors responsible for this story: John Walcott at jwalcott9@bloomberg.net Larry Liebert, Justin Blum