Bustillo said in a statement that he had submitted his resignation “to dispel any suspicion that, as an authority figure, I might exert undue influence over third parties, protected by the privileges of my position.”

He resigned after audios were revealed in which he appears to call on former deputy Foreign Minister Carolina Ache to not hand over her phone to investigators.

According to the audios, Bustillo was trying to make sure investigators wouldn't see conversations Ache had with another official relating to the granting of a passport to Sebastian Marset while he was detained in Dubai in 2021. That official had warned Marset was a “dangerous” drug trafficker.

Ache, who resigned last year, testified before prosecutors earlier Wednesday as part of an investigation into Marset's passport.

“I was the only politician in this government who resigned and went home. And, paradoxically, it was not because I had done something wrong nor illegal, quite the opposite. It was because I was not willing to conceal communications from the judiciary and because I refused to commit a crime,” Ache told journalists after she testified.

Following the release of the audios, leaders of the opposition called on President Luis Lacalle Pou, who is in the United States, to dismiss several top officials, including Bustillo and Interior Minister Luis Alberto Heber, among others.

Bustillo, who had been foreign minister since July 2020, claims Ache “decontextualized conversations and acted in bad faith” and insisted there was “nothing illegal” in the passport that was granted to Marset.

Bustillo said he would talk to the media after he testifies before prosecutors, which he is scheduled to do Friday.

“I will be available to the media to shed light on the accuracy of what has been done and on the distorted narrative that has been presented," Bustillo said in the statement he issued Wednesday evening.

Bustillo had previously testified before lawmakers that granting the passport to Marset involved an “administrative procedure” and was not political. He also alleged ignorance, saying that Marset's name was not as well known as it is now.

Authorities say Marset, 32, set up a criminal organization across Paraguay, Uruguay and Bolivia to export cocaine to Europe. He is also accused of being the mastermind behind the murder of Paraguay prosecutor Marcelo Pecci in Colombia in 2022.

Marset has eluded capture several times, most recently in August, when he was able to skirt an intense search in Bolivia, where authorities were embarrassed following revelations that he had been living in the country for months under a false identity.