Relations have always been strong between Azerbaijan and Turkey, and are often described as "one nation, two states" by the ex-president of Azerbaijan Heydar Aliyev due to both being Turkic countries. Turkey was one of the first countries to recognize Azerbaijan's independence on June 4, 1918 (Treaty of Batum) and the first to recognize Azerbaijan's restoration of independence from the Soviet Union in 1991. Since then, Turkey has been a staunch supporter of Azerbaijan in its efforts to consolidate its independence, preserve its territorial integrity and realize its economic potential arising from the rich natural resources of the Caspian Sea. The two countries share an long international borderline, with the Aras River separating Turkey from the Nakhchivan exclave of Azerbaijan. Nagorno-Karabakh conflict A war between Azerbaijan and neighbouring Armenia broke out shortly after the parliament of Nagorno-Karabakh, an autonomous oblast in Azerbaijan, voted to unify the region with Armenia on February 20, 1988. The Armenian demand to unify Karabakh with Armenia, which proliferated in the late 1980s, began in a relatively peaceful manner; however, as the Soviet Union's disintegration neared, the dispute gradually grew into a violent conflict between the ethnic groups in Nagorno-Karabakh, resulting in ethnic cleansing by all sides. The declaration of secession from Azerbaijan was the final result of the territorial conflict regarding the land. Following a UN Security Council resolution on April 6, 1993, calling for the immediate withdrawal of Armenian forces from the Azerbaijani district of Kelbajar, Turkey joined Azerbaijan in imposing the full economic embargo on Armenia, and the border between the two states was closed. The border subsequently remained closed, as Turkey demanded the withdrawal of Armenia from Nagorno-Karabakh and seven surrounding districts of Azerbaijan. Turkey made the demand a condition for establishing diplomatic relations with Armenia. Turkey supported Azerbaijan politically, supplied arms, and held joint military drills to improve combat interoperability since the 2020 Nagorno-Karabakh War. In September 2022 at a United Nations news conference, Turkish Defense Minister Hulusi Akar reiterated Turkey's support for Azerbaijan in its conflict with Armenia. Negotiations and economic co-operation Turkey supports the OSCE Minsk Group, as a mechanism for resolving the territorial dispute and views it from the principle of Azerbaijani integrity. It does not recognize the de facto independent republic of Nagorno-Karabakh that emerged, otherwise known as Artsakh. Turkey has supported various indirect bilateral talks between Azerbaijan and Armenia and initiated trilateral dialogue in Reykjavik in