Russia's Transport Ministry could levy a 20-30 percent tariff on coal shipped to export markets in order to fund the expansion of the railway grid, sources at the ministry and the RZhD state rail monopoly told Kommersant daily.

The sources told the newspaper in an article published on Thursday that Russia wants to raise funds in order to pay for new projects, including a rail line in the Siberian Republic of Tuva that will ship coal from new mining projects.

RZhD and the ministry could not be immediately reached for comments on the matter.

The sources did not say when the tariff might go into force, but Kommersant wrote that miners in the Kuznetsk Basin (Kuzbass), Russia's key coal producing region, estimate the tariff could cost them 19 billion roubles ($670 million) annually.

Russian coal exports rose by about 25 percent from 2006 to 115 million tonnes in 2010, putting considerable stress on the nation's Soviet-era rail lines.

Consultants at IMC Montan expect five major new export-oriented projects to boost the total amount of coal railed for the domestic and export markets by a further 70 million tonnes by 2020. (Reuters)