No discussions took place on US troop levels in South Korea when Defense Minister Jeong Kyung-doo spoke by phone with US Defense Secretary Mark Esper on Tuesday, the defense ministry said.

The 50-minute conversation came just days after the Wall Street Journal reported that the Pentagon has presented the White House with options to reduce troop levels in South Korea amid a deadlock in negotiations to share the cost of the American troop presence.

"No discussions took place related to (the US troop level) during today's phone talks, nor has it been discussed in the past," deputy ministry spokesperson Col. Moon Hong-sik said during a regular press briefing. "South Korea and the US have a firm shared understanding on the role and importance of US Forces Korea (USFK) for the peace and stability of the Korean Peninsula and the Northeast Asia region."

Talk of troop reduction came as the two countries have made little progress in efforts to narrow differences on how to share the cost of the upkeep of the 28,500-strong USFK.

Jeong and Esper agreed on the need to promptly conclude a new cost-sharing deal, according to officials. 

Later in the day, Esper said he has "issued no orders to withdraw forces from the Korean Peninsula."

"We will continue to look at adjustments at every command we have in every theater to make sure we are optimizing our forces,"

Esper said during a virtual event hosted by the International Institute for Strategic Studies.

Another key topic was how to hold annual summertime military exercises between the two countries amid coronavirus concerns. The two sides already skipped their annual springtime exercises earlier this year due to the pandemic.

"The two countries are closely coordinating on how to hold the combined training while taking various circumstances into consideration, including the COVID-19 situation," an official said.

"The two countries are closely coordinating on how to hold the combined training while taking various circumstances into consideration, including the COVID-19 situation," an official said.

Jeong and Esper also agreed to "unwaveringly" push for the agreed-upon transition of the wartime operational control (OPCON) of South Korean forces from Washington to Seoul, officials said, amid concerns that canceling or scaling back joint exercises could affect the envisioned OPCON transfer.

Seoul and Washington have been working for a conditions-based OPCON transfer. No specific deadline has been set, though many see the two sides eyeing 2022, or thereabouts, as the target date.

The right conditions required to be created before the OPCON transfer are South Korea's capabilities to lead the allies' combined defense mechanism, its capacity for initial responses to the North's nuclear and missile threats, and a stable security environment on the peninsula and in the region.

In order to verify whether Seoul is on course to meet the conditions for the transition, South Korea and the US carried out an initial operational capability (IOC) test in August last year, and they are planning to move on to the next step of carrying out a Full Operational Capability (FOC) test.

The two defense chiefs also shared their assessments of the security situation on the peninsula and vowed to continue supporting diplomatic efforts for denuclearization of North Korea and establishment of a lasting peace, it said.

"The two sides agreed to continue maintaining the South Korea-US alliance's readiness posture and combined defense posture to respond to the changing security situation on the Korean Peninsula," the ministry said in a release.

Jeong and Esper will continue discussions on pending issues during their annual Security Consultative Meeting slated for fall, the ministry said. (Yonhap)