“Ambassador Bass has our full backing, not only here at the State Department but also at the White House as well,” said Heather Nauert, the department spokeswoman.
The dispute began on Sunday after a Turkish employee of the United States Consulate in Istanbul was arrested and accused of having links to Fethullah Gulen, the Islamist cleric accused by the Turkish government of orchestrating a failed coup last year.
The consulate employee was the second to be detained this year. A third is being sought, and the police have questioned his family members, according to Turkish news reports.
The American Embassy dismissed the charges as baseless, and in response temporarily stopped issuing visas to Turkish citizens to travel to the United States while it assessed Turkey’s commitment to the security of American facilities and personnel.
Within hours, the Turkish Foreign Ministry announced similar measures in the United States, adding that the suspension included electronic visas and visas bought at the border, the way most tourists and other short-term visitors enter the country.
On Tuesday, Turkey seemed to have suspended its electronic visa service for Americans. But officials said by early afternoon that no Americans had been turned back since none had arrived without visas.
The Turkish government has been conducting a widespread crackdown under a state of emergency since the coup attempt in July 2016, arresting more than 50,000 people and suspending 150,000 for alleged links to the Gulen movement. It has also insisted on the need for wide-ranging investigations and purges to remove coup plotters and Gulen supporters from government institutions.
Military officers, politicians, journalists, academics and government workers have been caught up in the broad sweep, as well as several dozen foreign citizens, including 11 Americans.
Western officials have accused Mr. Erdogan of detaining foreign citizens as hostages or bargaining chips in order to secure the extradition of Mr. Gulen, who has been in self-imposed exile in Pennsylvania since the early 1990s.
Political analysts say Mr. Erdogan is also concerned about court cases in the United States against 15 of his bodyguards, who are accused of attacking protesters in Washington in May, and a group, including a former cabinet minister, charged with conspiring to break Iranian sanctions.
Adding to the tensions, a Turkish court on Tuesday sentenced a reporter for The Wall Street Journal to more than two years in prison over an article she wrote about the Kurds, the newspaper said. The court deemed the article to be terrorist propaganda in support of a banned Kurdish separatist organization.
The conviction of the reporter, Ayla Albayrak, who holds dual Turkish-Finnish citizenship and is currently in New York, “highlights the increasing targeting of journalists in Turkey,” the newspaper reported.
“This ruling against a professional and respected journalist is an affront to all who are committed to furthering a free and robust press,” said William Lewis, the chief executive of Dow Jones, the newspaper’s publisher. “We call on those who share this commitment to make their voices heard.”
Mr. Erdogan has used the attempted coup to rally political support and stir nationalist sentiment. Many of his supporters openly voice the suspicion that the United States had a hand in the plot and sought his downfall.
Mr. Erdogan said on Tuesday that Gulen followers had infiltrated the American Consulate in Istanbul, and he questioned why the United States had tolerated them.
“How did these agents infiltrate into the American Consulate?” he asked. “If these agents did not infiltrate the American Consulate, then who put them there? We need to focus on them. No state would allow such agents to threaten it from the inside.”
Prime Minister Binali Yildirim set an anti-American tone in comments to party members during a weekly meeting in Ankara.
Regarding the legal cases against the United States Consulate employees, he said: “So what? Is it a privilege to be in the U.S. mission? Should we get permission from those gentlemen?”
The United States authorities had never asked for Turkey’s permission when they detained an officer of a Turkish state-owned bank, Mr. Yildirim said. He was referring to the arrest in New York of Mehmet Hakan Atilla, the deputy general manager of International Banking at Halkbank, who is among those charged with conspiring to break sanctions on Iran.
Mr. Yildirim called for the diplomatic dispute to be resolved swiftly, through dialogue, but he also seemed to be rubbing salt in the wounds of the relationship. He told party members that around 80 percent of Turkish people do not like the United States. It had failed to cooperate with Turkey in the aftermath of the coup attempt and continued to support Kurdish fighters in Syria against Turkey’s request, he added.
A survey conducted recently by the Pew Research Group found that 72 percent of Turkish citizens felt that American power and influence were a major threat to their country, an increase of 28 percentage points since 2013.
The American suspension of all nonimmigrant visas could affect over 100,000 Turkish citizens who travel to the United States annually, but Turkey is likely to suffer more: Roughly half a million Americans, business travelers and tourists, visit Turkey annually.
But Turkey seems to have dialed back on its initial announcements that all visas would be suspended. Customs and Trade Minister Bulent Tufenkci said that no American without a visa would be allowed to enter the country, adding that none had tried so far. The airport police confirmed that no Americans had been turned back, since none had tried to arrive without visas.
Trade would not immediately be damaged since a lot of commerce was conducted electronically these days, Mr. Tufenkci said.
“The world is getting smaller now,” he said. “Everything is not connected to a visa.”