"Liaison officials from both sides made the first call of today at 9:30 am," said an official at Seoul's unification ministry.

"It was for checking technical aspects of lines. The North did not make any comment on talks."

The North could clarify its stance on Seoul's dialogue offer as early as Friday as the South and the United States agreed late Thursday to delay their joint military drills during the Winter Olympics.

The allies had been in consultations over whether to postpone the exercises that could coincide with the PyeongChang Olympics or the Paralympics.

North Korea has long denounced the military drills as a war rehearsal and used them as an excuse for its provocations. But the South and the US said that the exercises are defensive in nature.

In his New Year's Day speech, Kim called on South Korea and the US to suspend the military drills and halt Washington's regular deployment of strategic assets around the Korean Peninsula. His remarks could be viewed as the North's preconditions for talks.

North Korea is under tough international sanctions due to its defiant pursuit of nuclear and missile programs.

After a nine-year rule of two conservative governments, liberal President Moon, who favors engagement with Pyongyang, took office in May last year. But the North's nuclear and missile threats have prompted him to maintain the dual track of seeking sanctions and dialogue.

Seoul hopes that better inter-Korean relations can help pave the way for the resolution of North Korea's nuclear issue and broader talks between the US and North Korea.

Some experts said that the North's overture to South Korea may be aimed at weakening the united front in enforcing sanctions on Pyongyang and driving a wedge in the decadeslong alliance between Seoul and Washington.

During a phone conversation, Moon and President Donald Trump agreed Thursday to continue the US-led campaign of maximum pressure against North Korea and to "not repeat mistakes of the past." (Yonhap)