Ukrainian President Petro Poroshenko has signed a decree, ending Russian-Ukrainian Friendship Treaty.
The decree has been published on the official presidential website on Monday.
The decision was taken at a meeting of the country's National Defence and Security Council and is to be communicated formally to Russia and to the international community by the end of the month.
"Treaty on Friendship, Cooperation, and Partnership between Ukraine and the Russian Federation" was signed between Russian and Ukraine in 1997, describing the two countries as "strategic allies".
The treaty states that Russian and Ukraine "shall respect each other′s territorial integrity and reaffirm the inviolability of the borders existing between them".
In 2014, Russia annexed the Crimean Peninsula in violation of one of the principal articles of the treaty.
source: commonspace.eu with agencies
European Commissioner Johannes Hahn held discussions with officials from the South Caucasus on the margins of the Munich Security Conference