This photo, carried by North Korea's official Korean Central News Agency, shows the North firing the new Hwasong-19 intercontinental ballistic missile, Nov. 1. Yonhap

North Korea's recent launch of the Hwasong-19 intercontinental ballistic missile (ICBM) is believed to have taken place without a new engine test, a South Korean lawmaker said Monday, amid suspicions that Russia may have provided technical assistance to the North for the missile firing.

North Korea confirmed it had successfully test-fired the new Hwasong-19 ICBM on Oct. 31 and called it an "ultimate" version of its long-range missile series. The missile reached the highest altitude and flew for the longest time.

State media photos showed the missile being fired from an 11-axle transporter erector launcher (TEL) — assessed to be about 30 meters long — apparently bigger than any of the North's existing missile launch vehicles.

"Considering the increase in the length and diameter of the missile's fuselage and enhanced maximum altitude, the Hwasong-19 is assessed as a new type of ICBM that is different from the Hwasong-18," the Defense Intelligence Agency said in a report to Rep. Yu Yong-weon of the ruling People Power Party.

North Korea disclosed its test of new engines for missiles in the past, but the military said it has not detected signs of additional tests for solid-fuel engines since March 20, when the North's state media carried a report on a claimed ground jet test of a solid-fuel engine for a new type of intermediate-range hypersonic missile.

"It is assessed that the possibility of North Korea receiving support from Russia on technologies that can be applied to the development of ballistic missiles, under the name of 'space technology cooperation,' cannot be ruled out," the military said in the report.

North Korea appears to be accelerating its missile development with a focus on solid-fuel ICBMs that are considered to be harder to detect ahead of a launch compared with liquid-fuel ones as they require fewer preparation procedures, such as the injection of fuel.

North Korea launched the solid-fuel Hwasong-18 ICBM three times last year — in April, July and December. (Yonhap)