"Note: The official conventional long-form and short-form names remain “Republic of Turkey” and “Turkey”, respectively. “Republic of Türkiye” should be used in formal and diplomatic contexts. The conventional names may be used in place of or alongside “Türkiye” in appropriate instances, including U.S. government cartographic products, as it is more widely understood by the American public."
"Note: The official conventional long-form and short-form names remain “Republic of Turkey” and “Turkey”, respectively. “Republic of Türkiye” should be used in formal and diplomatic contexts. The conventional names may be used in place of or alongside “Türkiye” in appropriate instances, including U.S. government cartographic products, as it is more widely understood by the American public."
Source: https://www.state.gov/u-s-relations-with-turkey/