(CNN) — It’s the type of plot that defense hawks in the United States warn about: a potential cyberattack against the U.S. government orchestrated by none other than Venezuela, Iran and Cuba, with the help of a group of Mexican leftists.

The U.S.-based Spanish-language network Univision recently aired an investigative documentary alleging that Venezuelan and Iranian diplomats were interested in an offer from a group of Mexican hackers to infiltrate the websites of the White House, FBI, Pentagon and U.S. nuclear sites.

But the hackers were university students recruited to do the dirty work who decided instead to document the evidence to disrupt the plot, the documentary reported.

Venezuelan President Hugo Chavez has called the report “lies.” And one of the Iranian diplomats told Univision he indeed was presented with a hacking plot by the Mexican group but turned it down in part because he thought they were CIA agents.

The evidence that the plot was real, according to Univision, are secret recordings with diplomats who ask questions about what the hackers can do and promise to send information to their governments.

The United States said it did not know about the alleged plot but that it found the Univision allegations “very disturbing.”

However, “we don’t have any information, at this point, to corroborate it,” State Department spokesman Mark Toner said.

The United States monitors Iranian activities in the Western Hemisphere very closely, he said.

Univision interviewed a purported Mexican whistle-blower — a student at the National Autonomous University of Mexico named Juan Carlos Munoz Ledo. The student told Univision he was recruited by a leftist professor who wanted to wage cyberattacks on the United States and its allies.

Munoz secretly recorded a 2007 meeting with Mohammad Hassan Ghadiri, then the Iranian ambassador to Mexico, who appeared to show interest in what the hackers were capable of. In an interview with Univision, however, the former ambassador said his government rejected such a plot.

Munoz also recorded a meeting in 2008 with Livia Acosta, then-cultural attache of the Venezuelan Embassy in Mexico. According to the recording as aired on Univision, Acosta is heard saying that she can send the information gathered by the hackers straight to Chavez. Acosta is now the Venezuelan consul in Miami.

In response, a group of American lawmakers, organized by U.S. Rep. Ileana Ros-Lehtinen, R-Florida, has sent a letter to Secretary of State Hillary Clinton asking for an investigation into Acosta.

“If true, these actions demonstrate (Acosta’s) willingness to undermine U.S. interests and the potential threat to our national security posed by (her) activities,” the letter said. The lawmakers ask for Acosta to be dismissed from the country if the allegations are proven.

Venezuelan opposition presidential candidate Pablo Medina told CNN en Español that ties between his country and Iran are troubling.

“It’s an allegation that seems very serious to me,” he said.