The two countries, which regularly conduct joint military exercises, made a decision to postpone them during the Olympics - before talks between North and South Korea began.
"The South Korean and the USA government together announced that the joint exercises have been postponed based on Olympic spirit", Song said at a meeting of the National Assembly's National Defense Committee.
With the start date for the large-scale exercises yet to be confirmed, Seoul's Defense Ministry reported to lawmakers Tuesday that South Korea and the US will conduct their spring Key Resolve manoeuvres to defend against the North's missile threat, according to Yonhap News Agency.
At the same time, the document does not mention the larger Foal Eagle field exercises. North Korea views the exercises as a rehearsal for invasion, and has long used them as a pretext for its own provocations.
USKF Commander General Vincent Brooks last Wednesday pledged to conduct the joint military drills in a report submitted to U.S.'s House Committee on Armed Services. Key Resolve and Foal Eagle typically have begun in late February or early March, while Ulchi Freedom Guardian is held each year in August or September.
"Trump and his clique are racketeering to nip peace in the bud that started sprouting on the Korean peninsula", KCNA said in a commentary.
This was announced by the Defense Ministry in Seoul, quoted by the news agencies.
Both the South and North appear to be tip-toeing around these issues during the period of the Pyeongchang Olympics, he said.
The North also criticized a smaller Warrior Strike training exercise with US and South Korean troops that was held before the Olympics, calling it "nothing but a provocative act of war maniacs".
The Olympics have since seen a charm offensive by Pyongyang, which dispatched athletes, cheerleaders and its leader's sister Kim Yo Jong to attend the Games.
In a separate KCNA commentary, the North assailed the US and President Donald Trump for hinting at the possibility of military action to rein in Pyongyang's nuclear ambitions.
The North's response continued: "It is a provocative act of chilling the active efforts of the Democratic People's Republic of Korea and enthusiasm of the global community to defuse tension and create a peaceful environment".
Song denied suggestions that Seoul was reluctant to confirm the date due to fears of provoking Pyongyang, telling lawmakers that "we are not studying the pleasure of North Korea".