Former Prime Minister Yulia Timoshenko said her BYuT faction "will do everything we can to defend Ukraine against the introduction of Russia as a second state language," RIA Novosti reported.
Under proposed legislation, Ukrainian would remain the only state language, but restrictions would be lifted on the use of other languages spoken in the country, including Russian, Bulgarian, Romanian and Hungarian, granting them official regional status.
Many of the country's top politicians, including Prime Minister Mykola Azarov, cannot speak Ukrainian, and President Viktor Yanukovych is himself a novice speaker.
Russian is still used in much of the republic, especially in the east, the Crimea and the capital Kiev, and there is a strong movement to protect the rights of Russian speakers, the report said.
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