Russia on Friday dismissed constitutional amendments proposed by Kiev to decentralise Ukraine as part of the peace process as merely an "imitation" of compliance.

Ukraine's parliament on Thursday voted in favour of sending to the Constitutional Court a package of reforms that would grant greater autonomy to the war-ravaged separatist east.

The constitutional reforms will have to be voted on twice more by the Verkhovna Rada parliament -- and approved by 300 of 450 lawmakers -- but Moscow has indicated its displeasure with the measures already.

"The attempt to present the constitutional amendments... as some kind of fulfilment by Kiev of its Minsk obligations is just an imitation and should not fool anybody," said a statement on the foreign ministry website.

A peace accord struck in February in the Belarussian capital Minsk called on Kiev to see through a raft of measures to grant a special status to the rebel-controlled areas of Donetsk and Lugansk regions, including constitutional reform.

The Russian statement called the proposed amendments "political demagoguery" which aim to "mislead the Ukrainian and international public."

The vote ignited a storm of criticism in the Ukrainian parliament, including physical scuffles.

Kiev and the West blame Moscow for continuing violence in Ukraine's east, where some 6,500 people have been killed since the conflict between the separatists and Kiev's forces began last April.

Moscow has always denied sending troops or arms across the border.