Dmitry Fyodorovich Mezentsev (Russian: Дми́трий Фёдорович Ме́зенцев; born 18 August 1959)[1] is a Russian politician and diplomat serving since 2021 as the State Secretary of the Union State of Russia and Belarus.

[2][3] In 2012 Mezentsev ran for President of Russia, but was rejected by the Central Election Commission.

On 14 December 2011, the trade Union Committee of the East Siberian railway nominated Dmitry Mezentsev as a presidential candidate.

His candidacy was supported by the then President of Russian Railways Vladimir Yakunin.

[6] On 19 March 2021, Mezentsev was relieved of his post as ambassador to Belarus by presidential decree.