Seoul steps up military response after Pyongang's hydrogen bomb test

South Korean officials were said to be in discussions with the White House regarding the deployment of aircraft carriers and strategic bombers to the Korean peninsula after North Korea had shown no signs of slowing down its nuclear programme in the wake of its largest nuclear test to date.

The United Nations Security Council was set to meet later on Monday to discuss how to best handle North Korean leader Kim Jong-un's constant provocations and disregard for international mandates.

According to Jim Mattis, the United States's defence secretary, the president had requested he be briefed on all available military options as officials believed that activity around the launch sites suggested that Pyongyang had further ICBM tests planned.

"We have continued to see signs of possibly more ballistic missile launches. We also forecast North Korea could fire an intercontinental ballistic missile," said Jang Kyoung-soo, acting deputy minister of South Korea's national defence policy on Monday.

South Korean army and air force personnel conducted several live fire exercises involving long-range air-to-surface and ballistic missiles on Monday as a result of the North's nuclear test on Sunday.

Seoul was reportedly preparing to deploy the four remaining launchers of Washington's new missile defence system after the government had completed an environmental assessment, setting the stage for the full roll-out of the much discussed, oft maligned Terminal High-Altitude Area Defense system.

Mattis added that the US was considering stopping trade with any country doing business with the rogue nation, which relies on China to the north for about 90% of its foreign trade.

He finished by saying that the White House would respond to any threat "with a massive military response, a response both effective and overwhelming," but the president was "not looking to the total annihilation of a country, namely North Korea."

The Chinese government claimed to have launched a diplomatic protest with Kim over his hydrogen bomb, said to be between three and six times the size of the atomic weapon the wiped out Hiroshima in 1945, as South Korean president Moon Jae-in called the test an "absurd strategic mistake" while urging for the "strongest possible response."

Trump, on the other hand, threatened to pull out of a trade agreement with South Korea, firing shots at president Moon Jae-in.

Moon, who took office in May after former leader Park Geun-hye became the nation's first president to be impeached as a result of sordid collusion between political allies and corporate elites like Samsung, was opposed to deployment of THAAD but has pivoted as of late following intensified rhetoric and progress by the hermit kingdom to the North in its push for ICBMs capable of striking its US ally.

South Korea accurately fired a surface-to-surface ballistic missile and an air-to-ground rocket on a target in the East Sea on Monday, simulating a strike against the North's main missile-testing area.