Ukrainian language law makes it almost impossible for the Russian-speaking population [in Ukraine] to use the Russian language. This applies not only to the Russian language, but also to Hungarian and others […] That is, the law deprives people of their fundamental rights and freedoms. Moreover, the Constitution and the procedure of consideration were violated.
The Verkhovna Rada passed on April 25 the law "On ensuring the functioning of the Ukrainian language as a state language". The law establishes mandatory use of the Ukrainian language in most areas of public and communal life, including the mass media, education, science, etc.
However, the law does not forbid the use of Russian and other languages in private communication and religious ceremonies. Moreover, Russian and other languages can be present in book publishing, the press, including radio and television, education and the service sector. The law allows the use of other languages in the healthcare system and in law enforcement. Ukrainian language, though, is preferred.
In addition to this, the law stipulates that in accordance with the European Charter for Regional Languages and Languages of National Minorities, the government should develop a law safeguarding languages rights of minorities during the six months after the language law enters into force.
For background on the Ukrainian language laws, see here.