Turkish President Recep Tayyip Erdogan announced alongside his Ukrainian counterpart Volodymyr Zelensky on Wednesday that his country considered the 2014 Russian annexation of Crimea “illegal” and that Ankara would strive to help “our kinsmen’s existence in their historical motherland Crimea.”

Erdogan referred to the Crimean Tatars, a Turkic Muslim people who suffered exile to Siberia under Joseph Stalin and expressed alarm at the possibility of returning to Russia’s hands with President Vladimir Putin invaded and annexed the Ukrainian peninsula.

The Russian government maintains that the majority of Crimeans are ethnically Russian and wished to see the peninsula reunited with Moscow. Ukraine continues to insist that Russia invaded illegally and that Kyiv will one day restore the nation’s rightful map.

Erdogan’s effort to strengthen ties with Ukraine follows months of negotiations with Russia to purchase a S-400 missile system – a violation of NATO protocol, of which Turkey is a part – and delicate talks over the Syrian civil war, where Russia supports dictator Bashar al-Assad, who Erdogan has repeatedly referred to as a “terrorist.”

“Continuation of our kinsmen’s existence in their historical motherland Crimea, protection of their identity and culture, preservation of their basic rights and freedoms are Turkey’s priorities,” Erdogan said on Wednesday at a joint press conference with Zelensky in Ankara, according to Turkey’s state-run Anadolu news agency. Zelensky is in the city for a state visit, seeking stronger diplomatic and economic ties.

“Turkey has not recognized Crimea’s illegal annexation, nor will it recognize it,” Erdogan vowed. “Our Crimean brothers and sisters are an important element of the historic and human connections between Ukraine and Turkey.”

Erdogan also expressed support to Ukraine in its ongoing war with Russia on its eastern border, where Russian “separatists” that Russia claims are officially unaffiliated to it have waged war to secede for years. Erdogan insisted on an end to hostilities that was “in line with international law and Ukraine’s territorial sovereignty.”

Zelensky thanked Erdogan for his support and called Turkey a “good neighbor, sincere friend, and important strategic partner.” Zelensky also made a bid to Turkish businesses to invest in Ukraine.

The Moscow Times notes that a significant population of Erdogan’s constituents are Crimean Tatars, who met with Zelensky on Thursday for the opening of a representative office for the ethnic minority in Ankara.

“We will tirelessly draw the attention of the international community to the violation of Crimean Tatars’ rights by the Russian occupation authorities in Crimea,” Zelensky promised at the opening ceremony for the office. “We also carefully study the problems of displaced Crimean Tatars who were forced to leave Crimea because of Russian aggression. I assure you all: Ukraine will not leave the internally displaced persons alone with their problems.”

Zelensky also assured them that he will streamline the process for allowing Tatars to visit Crimea.

The Ukrainian president also addressed the Crimean Tatars’ resistance to Russian occupation in Crimea during his Ankara tour Wednesday, objecting to Russian media referring to them only as “Tatars” and expressing outrage that the annexation resurrected fears and memories of “all the sufferings that a society had to go through should have been ended already.” Stalin forced the Crimean Tatars into exile in 1944 deep into Siberia, killing half on the voyage across Asia.

Erdogan’s resistance to the Crimean occupation is not new, though significantly more vocal now than it was in 2014. At the time, Erdogan said he insisted in a meeting with Putin that Russia respect the “necessary rights” of Crimean Tatars, including not imposing the Russian language or the Russian Orthodox Church on them, but did not jeopardize diplomatic ties with Russia. Erdogan explicitly rejected a Russian-orchestrated referendum that alleged 97 percent of Crimeans approved of being colonized by Russia.

Russian-Turkish ties have also survived their disparate points of view in Syria, allowing continued trade and a controversial missile purchase that puts Turkey at odds with NATO. Erdogan insisted, after months of loud disapproval from the NATO coalition, on buying an S-400 Russian missile system, expected to be fully deployed in April 2020. NATO protocol requires that member nations all use interoperable military hardware to allow for cooperation in the event of any joint military venture; the S-400 system is not interoperable and no other NATO country will be able to use it.

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