Ukraine’s parliament has approved a motion presented by President Petro Poroshenko to end the country’s Treaty of Friendship with Russia.
As many as 277 out of 450 lawmakers on Thursday voted in favor of the motion. The bill required a minimum 226 votes to pass.
The approved motion implies that Ukraine will not seek to renew the friendship treaty after it expires on March 31, 2019.
The treaty, which was signed in 1997, established a strategic partnership between the two countries.
The agreement called for Moscow and Kiev to "respect the territorial integrity of each other and confirm [the] inviolability of current mutual borders."
The pact further urged the two countries to embrace relations "based on principles of mutual respect of sovereign equality, inviolability of borders, peaceful resolution of differences, without use of force or threat to use force."
Also on Thursday, the parliament adopted another additional bill unilaterally doubling Ukraine's territorial waters to 24 nautical miles, claiming that the measure seeks to increase the navy's operational efficiency.
Ukraine’s withdrawal from the treaty and unilateral doubling of territorial waters comes as the two countries are locked in political and territorial dispute.
On November 25, Russia seized three Ukrainian navy vessels in the Kerch Strait situated between the Sea of Azov and the Black Sea, accusing the ships of illegally entering its territorial waters.
Tensions have since risen, with Kiev imposing martial law in its border regions and barring Russian “men of fighting age” from entering the country.
NATO presence in Ukraine
Ukraine also called for further US-led NATO military presence in the region in response to the Kerch Strait incident.
On Thursday, the Pentagon announced that it had carried out an "extraordinary” observation flight "to reaffirm US commitment to Ukraine".
"Russia's unprovoked attack on Ukrainian naval vessels in the Black Sea near the Kerch Strait is a dangerous escalation in a pattern of increasingly provocative and threatening activity," said Pentagon spokesman Eric Pahon commenting on the US aerial operation.
Moscow says the United States is encouraging provocation between Russia and Ukraine over the recent confrontation. Foreign Minister Sergei Lavrov said Washington should mediate between Ukraine and breakaway regions instead of defending Kiev.
Russian President Vladimir Putin accused his Ukrainian counterpart Poroshenko of orchestrating the naval “provocation” in the Black Sea to bolster his popularity ratings before next year’s election.
The Strait of Kerch is a strategic route linking the Sea of Azov to the Black Sea where Russia has built a bridge to link the former Ukrainian territory of Crimea with the Russian mainland, east of the territory.
Since Crimea’s reunion with Russia in 2014, Moscow and Ukraine have disputed territorial access to the strait and the Sea of Azov.
Earlier this year, Ukraine also detained two Russian ships in the Azov Sea.
Moreover, Poroshenko claimed earlier this week that Moscow seeks to block the ports of Mariupol and Berdyansk and ultimately push inland into Ukraine to create a land corridor to the Crimean Peninsula, a charge Russia strongly denies.
The crisis between Russia and Ukraine started after a string of protests overthrew Ukraine’s democratically elected government in 2014 and replaced it with a pro-Western government.
The incident provoked an ongoing armed conflict in the predominantly Russian-speaking regions of eastern Ukraine and also led to Crimea's reunion with Russia following a local referendum later in 2014.
Kiev and its Western allies have since accused Moscow of channeling troops and armaments across the border into eastern Ukraine, a charge the Kremlin denies.
International efforts to restore peace to the region have so far failed and more than 10,000 people have been killed in eastern Ukraine conflict.