"Even the United States does not appear to see (war possibilities)," Chung Eui-yong, the chief of the National Security Office, was quoted by a ruling party spokesman as saying.

Chung made the remarks during his talks with Woo Won-shik, the floor leader of the Democratic Party, where he explained a set of measures Seoul has taken in response to the North's test last Friday of a long-range ballistic missile, the second in less than a month.

Earlier this week, US Senator Lindsey Graham told NBC that Trump cited the possibility of engaging in war with the hermit state if Pyongyang continues to target the US mainland with its evolving missile program.

Talk of war has also been fueled by the North's menacing rhetoric against Seoul and Washington that are gearing up to stage their annual join military exercise later this month. Pyongyang has long denounced the exercise as a "rehearsal for a northward invasion."

Kang Hoon-sik, the ruling party spokesman, told reporters that during his talks with Woo, Chung reiterated that the government would carry out an environmental impact assessment on the deployment of a US missile defense battery in a "principled, prudent" way.

Following the latest missile provocation, Moon ordered the "temporary" deployment of four additional launchers of the Terminal High Altitude Area Defense system in addition to the two already deployed launchers.

The presidential office has said that the deployment of additional launchers was a measure to respond to the North's provocation, but a final decision for the full-on THAAD deployment would be made after the environmental assessment, a process that could take more than a year.

After the meeting with Woo, Chung warned that the North would face tougher international sanctions, highlighting that last week's provocation came as the U.N. Security Council was exploring new sanctions in response to the North's July 4 missile launch.

Under a set of UNSC resolutions, Pyongyang is banned from conducting any tests using ballistic missile technology. (Yonhap)