LONDON (Reuters) - Russia's defence minister was briefly shown by state media at a meeting of top officials on Thursday after dropping out of public view for days during Russia's invasion of Ukraine.

       Sergei Shoigu, a close ally of President Vladimir Putin, is overseeing what Russia calls its "special military operation", but had not been seen in public since March 11, fuelling speculation about his whereabouts.

       The 66-year-old was shown on Thursday on a televised split screen of top officials as Putin spoke to his Security Council by video conference in footage released by RIA news agency.

       RIA made a point of zooming in on Shoigu in the top left-hand corner of a video screen set in front of Putin. The clip did not contain audio and did not show Shoigu speaking.

       The Kremlin said Shoigu had taken part in the Security Council meeting along with other top officials.

       Asked about Shoigu's whereabouts, the Kremlin said it was understandable that the defence minister was devoting less time to media appearances.

       "The defence minister has a lot on his mind right now. A special military operation is under way. Now is not really the time for media activity," spokesperson Dmitry Peskov said.

       Shoigu is a veteran of Russia's political landscape who rose to prominence as the head of the Emergencies Ministry in the 1990s after the collapse of the Soviet Union.

       Defence minister since 2012, he has sometimes been tipped as a potential successor to Putin in the Kremlin. He and Putin have been pictured in Siberia taking holidays together, fishing and picking mushrooms.

       (Reporting by Reuters)