The move comes amid hope of large-scale investment from Seoul into Siberia.
Officials from Russia and North Korea say the long-waited train connection is now almost ready.
The distance between capital city Moscow and key Siberian cities could shrink in plan envisaged by the Kremlin leader.
One estimate is half a million new jobs stemming from improvements to the Baikal-Amur Mainline link amid hopes of foreign investment.
The Russian government is to give priority to Siberia and the Far East as it puts modernisation on fast-forward, insists Dmitry Medvedev.
Proposals have been made for high speed trains to run on two routes between Omsk and Novosibirsk, and Novosibirsk and Krasnoyarsk.
Journalist Kate Baklitskaya today begins an epic 3 month tour of some of Siberia's most iconic places.