The U.S. Embassy in Turkey announced Sunday that it was suspending the issuance of non-immigrant visas in the country, the latest indication of a frayed relationship between Washington and Ankara.
In a statement, the embassy cited a reassessment of the "commitment of the government of Turkey to the security of U.S. mission facilities and personnel."
Hours later, the Turkish Embassy in Washington announced it too was suspending visa operations for U.S. citizens, using the same language as the statement from the U.S. Embassy in Ankara.
The moves come as the two North Atlantic Treaty Organization allies are increasingly at odds over the extradition of Fethullah Gulen, a Turkish cleric living in Pennsylvania whom Turkey blames for a coup attempt on July 15, 2016. Gulen denies any involvement.
Turkey also has accused the U.S. of backing the Kurdistan Workers Party, or PKK, which both countries have designated as a terrorist organization. The PKK has links with U.S.-backed Kurdish groups in northern Syria.
Last month, in a meeting with President Recep Tayyip Erdogan in New York, President Donald Trump said the two countries were "the closest we've ever been."
But over the last year, Turkish authorities have indicted two Turkish nationals working at U.S. diplomatic missions in the country, and at least a dozen U.S. nationals accused of ties to Gulen are being detained.
On Oct. 4, a prosecutor in Istanbul announced the indictment of Metin Topuz, a Turkish national who has worked as a translator at the U.S. Consulate in Istanbul, over charges of espionage, terrorism and attempted overthrow of the government. Topuz, prosecutors allege, spoke multiple times on the phone with a key fugitive in the July 15 coup attempt.
The investigation into that coup attempt has seen tens of thousands arrested and more than 150,000 public workers dismissed, and the imposition of a state of emergency that remains in place.
Topuz is also accused of being in contact with four police officers implicated in the coup investigations. The U.S. Embassy issued a statement after Topuz's arrest saying it was "deeply disturbed" by the "baseless" indictment, as well as "leaks from Turkish government sources aimed at trying the employee in the media rather than a court of law."
In March, prosecutors indicted Hamza Ulucay, a Turkish national who worked as a translator at the U.S. Consulate in Adana for 36 years; he was charged with belonging to the PKK.
On Sept. 28, the State Department updated its travel advice for Americans, saying they should "carefully consider the need to travel to Turkey at this time."
Among the Americans detained in Turkey is Andrew Brunson, an evangelical pastor who had lived in the country for more than 23 years, and is now accused of ties to Gulen; espionage; and attempted overthrow of the government.
Turkey has repeatedly called for the extradition of Gulen. Last month, Erdogan suggested Americans would be held by his government until Washington handed over the cleric.
The fact that Gulen has yet to be extradited has triggered widespread speculation in the Turkish press that Washington was behind the coup attempt.
Gulen, who has lived in Pennsylvania for nearly two decades, heads a movement that operates hundreds of charter schools and other businesses in the United States.
This March, Turkish officials accused the U.S. Consulate in Istanbul of hiding its relationship with Adil Oksuz, who was accused of being Gulen's chief for the coup attempt. Oksuz was detained briefly before being released after the coup attempt and has been a fugitive since.
Six days after the coup attempt, the U.S. Consulate called Oksuz to inform him his visa to the U.S. had been canceled, in response to Turkish requests to track his whereabouts. Turkish officials, as well as many of the country's news outlets, have continued to speculate about why the consulate called Oksuz.
Turkish media outlets have also called for the closure of the Incirlik military base in southern Turkey, which houses more than 2,000 U.S. troops, along with aircraft used in the military campaign against the militant group Islamic State in Syria and Iraq.