The statement from Oleh Synehubov, reported by Ukraine's public broadcaster Suspilne, followed a claim by the United States on Thursday that Russia had recently used short-range ballistic missiles (SRBMs) sourced from North Korea to carry out many strikes against Ukraine.

"We are conducting all the necessary examinations. I will say for now that the markings have been erased from these missiles, but what we can see (is that) the country which produced it is not the Russian Federation," Suspilne cited Synehubov as saying.

Ukraine has not confirmed the U.S. assertion the missiles are North Korean. Ukraine's air force spokesperson said on Friday morning that Kyiv did not yet have information about whether the missiles were North Korean.

(Reporting by Max Hunder and Yuliia Dysa; Editing by Alex Richardson and Angus MacSwan)