FILE PHOTO: Venezuela's Chief Prosecutor Tarek William Saab attends a news conference at the Supreme Court in Caracas, Venezuela January 29, 2019. REUTERS/Manaure Quintero

CARACAS (Reuters) - Venezuela’s chief state prosecutor said on Thursday an investigation had been opened into directors of state-run oil firm PDVSA, and its U.S. refiner Citgo, that the opposition-controlled congress appointed on Wednesday.

Prosecutor Tarek Saab, in comments broadcast on state television, announced “the opening of an investigation against people designated illegally as directors of PDVSA and Citgo.”

Saab also said they would investigate foreign ambassadors named by opposition leader Juan Guaido, who on Jan 23 invoked constitutional provisions to assume an interim presidency. President Nicolas Maduro says Guaido is leading a coup.