In a move likely to further strain relations between the United States and Venezuela, the State Department on Sunday said that it had ordered a Venezuelan diplomat based in Miami to leave the country.

Officials declined to give a reason for the expulsion of the diplomat, Livia Acosta Noguera, Venezuela’s consul general in Miami.

Last month a news report had asserted that Acosta had taken part in discussions about possible cyberattacks against the United States while she was stationed in the Venezuelan Embassy in Mexico.

The report, broadcast on Univision, a Spanish-language network, included fragments of what it said were taped conversations with Acosta. In response to the report, several members of Congress had called for an investigation and for the expulsion of Acosta if the allegations were proved to be true.

The State Department gave Acosta until Tuesday to leave the country. The Venezuelan government, however, was notified of the State Department decision on Friday, giving Acosta 72 hours to depart under standard diplomatic procedure, department spokesman Mark Toner said.

Acosta’s whereabouts were unclear on Sunday, and the Venezuelan consulate on Brickell Avenue was closed. Press reports published in Venezuela indicate that Acosta may have left for her country in late December, but there are no indications whether she later returned to Miami.

News of her expulsion had been released Saturday night by Roger Noriega, former assistant secretary of state for the Western Hemisphere, through his Twitter account.

Venezuela’s Ministry of Communication did not respond to interview requests, and Venezuelan President Hugo Chávez did not bring up the consul during his Sunday television program, Aló Presidente, which ran for almost six hours. Venezuela’s embassy in Washington, D.C., said any statement about Acosta’s expulsion would come from Caracas.

Meanwhile, at least one Miami-based Venezuelan organization urged the State Department to expand its probe into the dealings of other Chávez consular staff in the United States.

“We ask that they deepen their investigation into consular officials who remain and represent a threat to U.S. security and its residents. They will continue the actions developed by Livia Acosta on U.S. soil,’’ warned a statement from the Organization of Politically Persecuted Venezuelans in Exile.

The decision to expel Acosta was made one month after Spanish-language Univision Network broadcast a documentary about Iran’s alleged terrorist activities in Latin America, including a taped segment in which the consul reportedly asks an alleged Mexican hacker to give her the access codes to nuclear facilities in the United States.

In the tape, the alleged hacker says that he provided the secret codes and the location of each of the U.S. nuclear plants to Iran, and a voice many have attributed to Acosta is heard to say: “You should also give me that […] to send it to the president, or rather the chief of defense; the chief of presidential security is my friend.”

The tape was made when Acosta worked as cultural attaché at the Venezuelan embassy in Mexico. Documents obtained by El Nuevo Herald indicate that Acosta actually performed other functions there as well.

According to the documents, Acosta and vice consul Edgard González Belandria, who was in charge of issuing passports at the Miami consulate, were registered in the savings bank of the Bolivarian Intelligence Service (known by its Spanish-language acronym SEBIN) — an indications that they are on the intelligence service’s payroll.