A leading Venezuelan opposition figure is to face charges over an alleged plot to assassinate the country's president, Nicolas Maduro.

Maria Corina Machado, a former congresswoman, was ordered by the country's chief prosecutor Wednesday to appear in court on Dec. 3 to be formally charged.

Machado, along with three other people who are the subject of arrest orders in connection to the alleged plot, have denounced the allegations as an attempt by Venezuela's government to silence its critics.

Allegations of a plot first surfaced in May, after Venezuela had been rocked by months of anti-government protests. Venezuelan officials produced emails, which they claimed were a conversation between Machado, other opposition figures and U.S. State Department officials, discussing a plot to overthrow the Socialist Party-led government, according to the Associated Press.

One of the men accused of involvement in the plot, Pedro Burelli, a former director of Venezuela’s state oil company who now resides in the U.S., hired a forensic cyber-security expert to examine the emails. The expert concluded that the emails had been faked, according to the Wall Street Journal.

“We reject the accusation completely and the fact that the allegations are fake was already certified by the Google data,” Tomás Arias, a lawyer for Machado, told the paper Wednesday.

Machado said on her Twitter account, that the charges amounted to political retribution against her, for calling for new leadership at Venezuela's state elections council.

Venezuela's Socialist Party, formerly led by the late Hugo Chavez, has on several occasions in the past made sensational allegations against its political opponents, without presenting any convincing evidence to back up its claims, according to a Reuters report.

In addition to social instability, Venezuela has faced a challenging economic situation this year. Prices for oil, the country's largest source of revenue, have fallen sharply, raising the prospect that the country would default on its foreign debt.

Maduro denounced such concerns as being part of a plot by foreign media, the Reuters news agency in particular, “to destroy Venezuela.”

In recent months the country has suffered from shortages of food and consumer goods, as up to 40 percent of the goods the country subsidizes for its domestic market are smuggled into neighboring Colombia, where they can be sold for much higher prices.