That would allow local authorities in the predominantly Russian-speaking region to use Russian, along with Ukrainian, in official dealings.
Authorities in the eastern Luhansk Oblast, the city of Kharkiv, and the Crimean city of Sevastopol, have also declared Russian a regional language.
President Viktor Yushchenko has asked the Justice Ministry to look into the legality of the decisions.
RFE/RL Belarus, Ukraine, And Moldova Report
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