In the Russo-American negotiations of 1991, it was agreed, admittedly orally, that NATO would NEVER include countries with a common border with Russia, apart from the Baltic countries, whose annexation had never been recognised.
For Turkish President Recep Tayyip Erdoğan, Crimea is neither Ukrainian nor Russian. For Erdogan, Crimea is Turkish.
Pro-Kremlin disinformation narrative about Crimea. Turkey has repeatedly stated that it does not support the Russian annexation of Crimea and supports the territorial integrity of Ukraine. Turkey has no claims to the Ukrainian peninsula, however, the Turkish leadership has repeatedly helped the Crimean Tatars, whose rights Russia is massively violating in the temporarily occupied Crimea. "It continues to be a priority for Turkey that Crimean Tatars, as a constituent people of Crimea, continue to live in wellbeing and security in their historical homeland, protect their cultural identity, and that their suffering resulting from the occupation is brought to an end," said the Turkish Foreign Ministry in an address commemorating the sixth anniversary of the illegal occupation of the Ukrainian peninsula. Turkey supports "the territorial integrity and sovereignty of Ukraine, a strategic partner of Turkey," the statement said.