South Korea's top security officials are beginning to lean towards strengthening military measures rather than dialogue with North Korea in response to the wayward regime's latest nuclear test, Seoul's defense minister said Monday.

His remarks came amid growing calls for President Moon Jae-in to make a course correction of his rapprochement policy that seeks to address the decadeslong nuclear standoff through a delicate mixture of sanctions and dialogue.

"During a National Security Council meeting (held shortly after the nuke test Sunday), views converged on a direction that strengthens the military standoff (for now), rather than (pursuing) the Berlin declaration or dialogue," Defense Minister Song Young-moo told a parliamentary session.

The Berlin initiative refers to Moon's policy that pursues Pyongyang's denuclearization with a security guarantee and economic and diplomatic incentives while seeking a peace treaty and dismissing the prospect of forced unification. 

During the session, Song also said that during his recent talks with US Defense Secretary James Mattis, he demanded the US

deploy its strategic assets to Korea on a "regular" basis. He made the demand, citing local politicians' calls for the redeployment of US tactical nukes.

But he dismissed the news report that during the talks in Washington he demanded the redeployment of the US nuclear arsenal that had been withdrawn from the peninsula in the early 1990s.

Seoul has rejected it based on its denuclearization principle.

Tensions sharply escalated Sunday as the communist regime conducted what it claims to have been a test of a hydrogen bomb mountable on an intercontinental ballistic missile. The test was only the latest in a recent series of saber-rattling, including two ICBM tests in July.

In its report to the legislature's defense committee, the defense ministry said that it, in consultation with Washington, will seek to deploy a nuclear-powered aircraft carrier, strategic bombers and other powerful assets to the peninsula as a response to the North's nuclear experiment.

It also unveiled its plan to stage unilateral live-fire drills involving Taurus air-to-surface guided missiles mounted on its F-15K fighter jets. The missile, with a range of 500 kilometers, is capable of launching precision strikes on the North's key nuclear and missile facilities.

In his assessment of the sixth nuke test, Song said that the North is presumed to have reduced the weight of a nuclear warhead to below 500 kilograms.

"Yes, we presume so," he said. "The smaller it becomes, the better it gets."

Song added that the North's warhead is seen as being able to be fitted onto an ICBM.

In its parliamentary report, the ministry also said that it has continuously detected signs of the North's preparations for ballistic missile launches.

"To show that it has secured a delivery vehicle that can target the US, the North could launch an ICBM-class ballistic missile,"

the ministry said.

Referring to the North's sixth nuclear test, the ministry estimated the test's yield at 50 kilotons, much stronger than the previous test last September, which was estimated at 10 kt. One kiloton is equivalent to 1,000 tons of TNT. (Yonhap)