Russian Federation has been one of Maduro's staunchest supporters, providing the South American country with loans and weapons.
"Donald Trump has without doubt given an order to kill me and has told the government of Colombia and the Colombian mafia to kill me", Maduro told RIA. Venezuela's top prosecutor asked the country's Supreme Court to freeze Guaido's assets and bar him from traveling.
In a tweet earlier Tuesday, US National Security Adviser John Bolton warned of "serious consequences" if the investigation request from Saab, who Bolton called an "illegitimate former Venezuelan Attorney General", was approved.
Mr Guaido has thus far managed to avoid arrest and the Supreme Court did not strip him of his legislative immunity, though the new investigation could signal that Mr Maduro's administration is moving to take a more punitive approach.
Worldwide support: Guaido's move has received backing across the globe.
Guaido-the 35-year-old leader of the opposition-controlled National Assembly-called for an election when he declared himself interim president of Venezuela last week.
"We must take to the street", he said.
Inside Venezuela, Maduro holds the reins of power with the armed forces still loyal despite an opposition push to lure their support by proposing amnesty for anybody who supports Guaido's transitional government.
That followed the United States' decision to hand control of Venezuela's U.S. bank accounts to Guaido, barring Maduro from accessing the funds.
Fuel in Venezuela is practically free: one dollar can buy more than 300 million liters of fuel but only a kilogram (2.2 pounds) of onions.
Maduro called the sanctions "criminal" and vowed to challenge the United States in court.
Chinese foreign ministry spokesman Geng Shuang said his country opposes "unilateral sanctions" as they "will only complicate the situation and will not help solve practical problems".
Several smaller protests were held throughout the capital Caracas including in the neighbourhood of Altamira in the eastern part of the city.
Last week, a group of soldiers rose up against Maduro.
The sanctions mean the state-run company may not be able to fulfil contracts with North American buyers, the Government of President Nicolas Maduro said.
Describing himself as an admirer of U.S. history, Maduro said that he hopes that reasonable USA citizens will prevail, adding that America "is a great country, and it is much more than Donald Trump". PDVSA bonds could be excluded from key indexes, also impacting sovereign paper, Bank of America Merill Lynch (BAML) said.
One of Maduro's most prominent supporters, Diosdado Cabello, said in a speech on Wednesday that the only elections the government is considering are for National Assembly, now the only opposition-controlled body in Venezuela. Guaido declared himself Venezuela's rightful leader a week ago and says the nation "is set on change".
Effectively sidestepping his U.S. counterpart, Maduro urged Americans to second-guess the distorted narrative peddled by the mainstream media.
Sorbay Pailla said she last heard from her husband, retired National Guard Col. Oswaldo Garcia Palomo, on Sunday after he entered the country clandestinely from Colombia. State TV broadcast pictures of him with his military.