The opposition leader's statements are considered by the prosecutor's office in Caracas to constitute "treason against the homeland" and "conspiracy with foreign power".
Machado has been in hiding for some time.
The investigation against her began after the US House of Representatives approved a federal embargo on Monday against business with Maduro's government and individuals linked to it. The proposal needs to be approved by the US Senate and President Joe Biden to come into effect.
According to Maduro's government, the sanctions law, if it comes into effect, constitutes a violation of the UN Charter.
The opposition in Venezuela claims that their presidential candidate Edmundo González Urrutia, who fled to Spain after an arrest warrant, won the election in July with 67 percent of the votes.
The Biden administration announced this week that it regards González Urrutia as the country's democratically elected president.
