The Treaty on Friendship, Cooperation, and Partnership between Ukraine and the Russian Federation is a since April 2019 expired agreement between Ukraine and Russia, signed in 1997, which fixed the principle of strategic partnership, the recognition of the inviolability of existing borders, and respect for territorial integrity and mutual commitment not to use its territory to harm the security of each other. The treaty prevents Ukraine and Russia from invading one anothers country respectively, and declaring war. Ukraine announced its intention not to renew the treaty in September 2018. By doing so the treaty did expire on 31 March 2019. The treaty was also known as the "Big Treaty". Until 2019 the treaty was automatically renewed on each 10th anniversary of its signing, on the condition that one party advised the other of its intention to end the treaty six months prior to expiration. Russia–Ukraine relations have deteriorated since the 2014 Russian annexation of Crimea and Russian support for separatist forces in the war in Ukraine's Donbass region. In response, Ukrainian PresidentPetro Poroshenko signed a decree not to extend the treaty.
Under the agreement both parties ensure the citizens of the other countries' rights and freedoms on the same basis and to the same extent that it provides for its citizens, except as prescribed by national legislation of States or international treaties. Every country protects in established order of the rights of its citizens living in another country, in accordance with commitments to documents of the Organization for Security and Co-operation in Europe and other universally recognized principles and norms of international law, agreements within the Commonwealth of Independent States. The agreement, among other things prematurely confirms the inviolability of borders of countries, regardless that Russia and Ukraine have never agreed on the final ratification and demarcation of a border between the two countries. Under Article 2: The Treaty document stipulates in Article 40 that the Treaty is entered into for a period of 10 years and renews automatically unless one of the parties notifies the other of its intention to curtail the Treaty.
Termination
On 19 September 2018, Ukrainian President Petro Poroshenko signed a decree not to extend the treaty. On December 3, 2018, President Poroshenko drafted a legislation to Parliament to end the Treaty of Friendship immediately as well as drafting legislation to parliament to declare war on Russia; with support coming from Western allies within the United Nations Security Council. According to Poroshenko the non-renewal "does not require a vote" in the Ukrainian parliament Ukraine announced that on 21 September 2018, it would notify the United Nations and other relevant organizations on the termination of the treaty. Russia's Ministry of Foreign Affairs said that it was notified on 24 September 2018 of the treaty's termination by Ukraine, expressing regret. On 3 December 2018 Poroshenko did submit a bill on the termination of the treaty to parliament; 277 MPs support the termination of the treaty, while 20 legislators voted against it.