AI impersonator posed as US Secretary of State Rubio, contacted Foreign Ministers

A person using artificial intelligence to mimic the voice of U.S. Secretary of State Marco Rubio reportedly contacted multiple foreign ministers and American officials last month, posing as the nation’s top diplomat.

According to a confidential diplomatic cable reviewed by Reuters, the individual used AI-generated voice cloning technology to impersonate Rubio and reached out via the encrypted messaging app Signal.

At least three foreign ministers, one U.S. governor, and one member of Congress were targeted in the scheme.

In several cases, the impersonator left voicemails that sounded convincingly like Rubio and attempted to initiate follow-up communication. One target received a message encouraging them to move the conversation to Signal, a tactic often used in social engineering campaigns to avoid detection.

A State Department spokesperson confirmed that the agency is investigating the incident and has begun alerting foreign governments through diplomatic channels. While no official comment was given on the identity of the impersonator or their motives, officials familiar with the matter said the incident has raised fresh concerns about AI-enabled disinformation, especially targeting diplomatic and political figures.

“We are aware of the impersonation attempts and are actively working to determine the source and intent behind them,” a senior State Department official said on condition of anonymity.

There is no indication that classified information was accessed, but the incident has renewed calls within the department and Congress for tighter authentication protocols in sensitive communications.

Not the first incident

This is not the first time high-profile political figures have been impersonated using AI-enhanced techniques.

In 2023, a deep fake video of President Joe Biden surfaced online during the early stages of the presidential primary season. In the video, Biden appeared to discourage voters from participating in a key state’s primary election.

The clip, later exposed as a Russian-linked disinformation operation, was widely shared before being removed. U.S. intelligence agencies concluded it was part of an attempt to undermine democratic trust and influence political discourse.

Similarly, in late 2022, a deep fake audio recording surfaced purporting to capture Ukrainian President Volodymyr Zelensky urging his forces to surrender to Russia. That recording was broadcast briefly on hacked regional television channels before it was debunked by Kyiv and NATO officials.

In 2024, impersonators used a cloned voice of French President Emmanuel Macron to contact European officials ahead of a major EU security summit, though no major security breach was reported. That episode prompted several European governments to review their secure

communication procedures, particularly for ministers and heads of state.

Experts warn that the growing accessibility of voice-cloning and deep fake video tools poses a significant threat to diplomatic integrity, national security, and public trust.

“With just a few minutes of audio, a bad actor can create a convincing replica of a government official,” said Dr. Elise Warren, a cybersecurity and AI researcher at Georgetown University.

“These impersonation attempts are no longer crude. They’re increasingly indistinguishable from real communication unless verified through multi-factor authentication.”

The incident involving Rubio comes amid growing pressure on the U.S. government to implement standards for authenticating official communications, especially across messaging apps commonly used by diplomats and lawmakers. Some agencies have already begun deploying digital watermarking tools and blockchain-based identity verification systems to prevent manipulation.

As of Tuesday evening, Rubio’s office had not issued a public comment on the impersonation attempt.

Rubio, a former senator from Florida, was appointed Secretary of State in early 2025 by President Donald Trump during his second administration. He has been at the center of high-stakes negotiations in recent months, including talks with NATO allies and Pacific partners.