The Ukrainian parliament has voted on Thursday not to prolong a friendship treaty with Russia, which is due to expire in the coming months.
A total of 277 parliamentarians out of 450 supported the move, according to Kiev-based UNIAN news.
The move came after Moscow seized three Ukranian navy vessels late last month.
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In the latest escalation of the confrontation between the two neighbors, Kiev's parliament adopted a bill that unilaterally doubles the extent of Ukraine's territorial waters.
Meanwhile, Ukraine urged dozens of foreign ministers attending a recent regional security conference to increase sanctions against Russia, accusing Moscow of ramping up aggression.
A member of the Ukrainian State Border Guard Service stands guard at the Goptovka crossing point on the border between Russia and Ukraine, November 28, 2018. /VCG Photo
Russia, however, insisted that Ukraine's actions in the Azov Sea were a "provocation."
What is the friendship treaty?
Signed in May 1997, the Treaty on Friendship, Cooperation and Partnership obliged Russia and Ukraine to "respect the territorial integrity of each other and confirm the inviolability of current mutual borders."
The document, which entered into force in April 1999 for a term of 10 years, could be automatically extended for 10-year periods provided the parties did not object, TASS news agency reported.
In October 2018, the period expired for the parties to announce their plans either to extend the treaty for another 10-year term or denounce the document. Ukraine chose to do the latter, it added.