Seoul, April 14 : North Korea said on Friday the missile used in its recent launch was its new solid-fuel Hwasong-18 intercontinental ballistic missile (ICBM), with leader Kim Jong-un saying that the weapon will "radically promote" the country's nuclear counterattack posture. The North launched the new ICBM on Thursday, guided by its leader Kim, in a test of "the future core pivotal means" of war deterrence, according to the Korean Central News Agency (KCNA). It did not reveal details of the missile's specifications, such as flight distance and maximum altitude, Yonhap News Agency reported. South Korea's military said Thursday it detected the North's launch of an intermediate-or longer-range ballistic missile in the vicinity of Pyongyang into the East Sea. The missile, fired at a lofted angle, flew about 1,000 kilometers, it said. The new ICBM will "radically promote the effectiveness of its nuclear counterattack posture and bring about a change in the practicality of its offensive military strategy," Kim was quoted as saying by the KCNA in an English-language dispatch. While expressing "satisfaction" with the launch, the North's leader vowed that Pyongyang will take "fatal and offensive counteractions" so that its enemies suffer from "extreme uneasiness and horror," it added. The test marked the recalcitrant regime's latest apparent progress to develop a solid-fuel ICBM, which is one of the five major defense projects it put forward at a key party congress in January 2021. Solid-fuel missiles are known to be harder to detect ahead of a launch, compared with liquid-fuel ones that relatively take more time during preparation. In December, Pyongyang tested a solid-fuel engine for a new strategic weapon and displayed a new ICBM during its military parade in February, raising speculation whether it employed a solid-fuel engine. The KCNA said the latest test-firing aimed to confirm the "performance of the high-thrust solid-fuel engines for multi-stage missiles and the reliability of the stage-jettisoning technology and various functional control systems." The missile's first stage landed in waters 10 kilometers off Kumya County, South Hamgyong Province, while the second stage fell into waters 335 km east of Orang County, North Hamgyong Province, according to the KCNA. The latest launch came just days ahead of the 111th birthday of the late Kim Il-sung, the North's national founder and the current leader's grandfather, on Saturday. It also came amid heightened tensions on the Korean Peninsula as the North has not responded to routine cross-border calls through inter-Korean liaison and military communication lines since last Friday. Pyongyang has recently conducted other major weapons tests, such as the launch of the Hwasong-17 ICBM on March 16 and what it claimed to be underwater nuclear attack drones, in protest against combined springtime military drills between South Korea and the US. /IANS