North Korean leader Kim Jong Un visits the exhibition of utensils and tools, finishing building materials and sci-tech achievements organised by the Ministry of the People's Armed Forces in this undated photo released by North Korea's Korean Central News Agency (KCNA), May 13, 2017. KCNA/via REUTERS

BEIJING (Reuters) - Russian President Vladimir Putin is concerned about Sunday’s missile test by North Korea, a Kremlin spokesman said on the sidelines of a visit by Putin to Beijing.