South Korea's defense ministry maintained a cautious approach Thursday toward springtime joint exercises with the United States amid preparations for a second summit between Washington and Pyongyang.

Seoul and Washington have been discussing how to proceed with their combined exercises, counting on their potential impact on ongoing diplomacy for Pyongyang's denuclearization and peace on the divided peninsula.

The Seoul-based conservative daily Chosun Ilbo reported that the two-week Key Resolve command post exercise, set to begin on March 4, could be postponed and that the Foal Eagle field exercise, slated to occur between March and April, could be scaled back.

"As we said earlier, we will make an announcement on the exercise plans at an appropriate time when a decision on concrete details is made," Choi Hyun-soo, the ministry's spokeswoman, told a regular press briefing.

Asked if the preparations for the Feb. 27-28 summit between US President Donald Trump and North Korean leader Kim Jong-un in Vietnam will be a variable that the allies need to consider in planning their exercises, Choi said, "Let's wait and see."

US Special Representative for North Korea Stephen Biegun is currently in Pyongyang to hash out details on the agenda and other details for the summit likely to focus on fleshing out the North's denuclearization steps and the United States' corresponding measures for the steps.

Speculation has persisted that the allied exercises could be called off, postponed or downsized amid concerns that the exercises, if pressed ahead with, could hurt efforts to denuclearize the North and pave the way for a lasting peace on the peninsula.

Pyongyang has long decried the allied exercises as a "rehearsal for invasion."

Last year, Seoul and Washington suspended a set of major exercises, including the summertime Ulchi Freedom Guardian exercise and wintertime Vigilant Ace air exercise, though they continued smaller-scale drills to maintain combat readiness. (Yonhap)