Venezuelan President Nicolas Maduro said on Tuesday he had ordered a "revision" of diplomatic relations with the United States and would announce new measures.

Maduro was responding to comments made earlier on Tuesday by U.S. Vice-President Mike Pence, who gave his support to Venezuela's opposition and called Maduro a "dictator with no legitimate claim to power."

Pence issued a video message of support to Venezuelans to encourage those who are protesting against Maduro and underline U.S. backing for opposition leader Juan Guaido.

Venezuela's opposition plans to hold marches nationwide Wednesday as part of an annual event that marks the fall of a military government in 1958. Government critics are increasingly comparing Maduro to dictator Marcos Perez, who was pushed from power that year.

As the good people of Venezuela make your voices heard tomorrow, on behalf of the American people, we say: estamos con ustedes. We are with you. We stand with you, and we will stay with you until Democracy is restored and you reclaim your birthright of Libertad. <a href="https://t.co/ThzIAqBoRn">pic.twitter.com/ThzIAqBoRn</a> —@VP

In the taped video message in English with a few Spanish words and phrases mixed in, Pence, who has lashed out at Maduro before, declared him a "dictator" who has no rightful claim to power.

"On behalf of President Donald Trump and all the American people, let me express the unwavering support of the United States as you, the people of Venezuela, raise your voices in a call for freedom," Pence said after offering a greeting of "hola," which means "hello" in Spanish.

"Nicolas Maduro is a dictator with no legitimate claim to power. He has never won the presidency in a free and fair election, and has maintained his grip of power by imprisoning anyone who dares to oppose him."

U.S. Vice President Mike Pence voiced support for opposition leader Juan Guaido in a videotaped message to the Venezuelan people today. (Manaure Quintero/Reuters)

Pence declared U.S. support again for Guaido, with whom he spoke by phone earlier this month, and the National Assembly, which he leads, as the "last vestige of democracy." Pence said Washington supported Guaido's decision to assert the body's powers, declare Maduro a "usurper" and push for a transitional government to be established.

"As you make your voices heard tomorrow, on behalf of the American people, we say to all the good people of Venezuela: estamos con ustedes," Pence said, following up with the translation in English: "We are with you, we stand with you, and we will stay with you until democracy is restored and you reclaim your birthright of libertad."

Maduro was inaugurated on Jan. 10 amid worldwide criticism that his leadership was illegitimate after a 2018 election that was widely viewed as fraudulent.

Pence has largely taken the lead within the Trump administration in condemning Maduro. He called the inauguration a sham and made clear the United States did not recognize the election result.