South Korean and US defense officials discussed possible space cooperation between Pyongyang and Moscow during a bilateral tabletop exercise on space this week, Seoul's defense ministry said Wednesday.

Choi Byung-ok, head of the ministry's defense policy bureau, and John Hill, US deputy assistant secretary of defense for space and missile defense, led the discussion-based exercise, as well as working-level talks, from Tuesday to Wednesday at the ministry in central Seoul.

The exercise came after North Korean leader Kim Jong-un met Russian President Vladimir Putin at Russia's Vostochny space center last Wednesday, raising concerns of possible space cooperation as Pyongyang has vowed to put a military spy satellite in orbit this year.

During the exercise, the allies improved their "unified understanding" on ways to respond to and deter potential threats from space and discussed the direction of their cooperation in the domain over the mid-to-long term, it said.

"The two countries also paid attention to the recently identified possibility of space cooperation between North Korea and Russia and shared their assessments on related activities," the ministry said in a release.

After the exercise, they held a session of the allies' regular Space Cooperation Working Group and discussed ways to enhance space cooperation as set out by their defense chiefs during the Security Consultative Meeting (SCM) last year.

At the SCM, Defense Minister Lee Jong-sup and US Defense Secretary Lloyd Austin pledged to explore cooperative measures to strengthen space capabilities as an alliance.

North Korea has vowed to launch a military spy satellite next month after two failed attempts in May and August. (Yonhap)