Venezuela's top opposition-appointed diplomat to the United States called on the "free world" Tuesday to "liberate" his country.

Charge d’Affaires Carlos Vecchio made the plea after a one-hour White House meeting with Vice President Mike Pence, as the Trump administration continues to dodge questions about potential military action to depose socialist leader Nicolas Maduro.

"We cannot do this alone. We have the main responsibility as Venezuelans, but we are asking the free world to liberate in a certain way Venezuela, which has been colonized by the Cuban regime," said Vecchio.

National Assembly leader Juan Guaido declared himself Venezuela's interim president last week and was recognized as such by President Trump and the leaders of many regional countries, including Brazil and Colombia. But the claim was rejected by Maduro, who retains control of the institutions of government.

Pence walked Vecchio onto the White House driveway and shook his hand, but did not address reporters.

Vecchio said that during his meeting with Pence, "We were so clear that this fight is not about ideology. This is a fight between democracy and dictatorship. This is a fight between a dictatorship that is totally controlled by the Cuban regime against the free world."

Vecchio did not directly address possible military intervention, but expressed concern that Guaido will be arrested "in the hours to come," following the filing of a criminal petition against him, and said 35 people have already died, with another 800 arrested during opposition protests.

Although persistently vague on potential use of force, White House national security adviser John Bolton warned Monday that there would be a "significant response" if Guaido was harmed, refusing to rule out U.S. military intervention in Venezuela's internal power struggle.

"The United States will hold Venezuelan security forces responsible for the safety of all U.S. diplomatic personnel, the National Assembly, and President Guaido. Any violence against these groups will signify a grave assault on the rule of law and will be met with a significant response," Bolton said.

Maduro was elected to a second term as president last year, though political opponents largely boycotted the election amid an economic collapse and exodus of refugees. After opposition parties won National Assembly elections in 2015, Maduro created a rival Constituent Assembly packed with supporters.