Nazarbaev told participants at an international economic forum in St. Petersburg that such a canal would be 1,000 kilometers shorter than sending goods via Russia's Volga-Don canal network.
He said Central Asia and Caspian states are rich in energy resources but need a range of options to deliver them.
Nazarbaev agreed recently to a plan that envisages the construction of a new pipeline and the modernization of old ones to carry Turkmen and Kazakh natural gas to Russia and on to Europe.
Some Western governments have sought alternative routes for energy shipments that would bypass Russia.
RFE/RL Central Asia Report
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