A Venezuelan volunteer places a bag of USAID humanitarian aid for storage at a warehouse next to the Tienditas International Bridge, near Cucuta, Colombia, on the border with Venezuela, Friday, Feb. 8, 2019.
US President Donald Trump even ordered the seizure of billions of dollars worth of Venezuelan assets found on US soil, and imposed punitive sanctions against the country.
Speaking in its inaugural meeting in the Uruguayan capital of Montevideo, the EU-backed International Contact Group on Venezuela said overly forceful intervention could aggravate the crisis in the country.
US humanitarian aid destined for Venezuela is now sitting in a warehouse on the Colombian border.
The rapid and precipitous endorsement of Guaido's claim on the presidency of his country by the U.S. and several European and Latin American countries makes a mockery of recognised worldwide norms. The world watches now whether Maduro's government will let the first shipments from United States cross its borders.
Guaido called the situation "an emergency ... a crisis", on Monday and said humanitarian aid would begin to flow into Venezuela in the coming days, defying Maduro's repeated refusal of assistance in the face of food and medicine shortages.
"I am not only saying that Maduro is a threat to the maintenance of peace of the region", he said. "The other practical problem we face is that, given the sanctions, we should no longer manage Venezuela from the United States ... but from Europe".
On the other hand, Maduro said that U.S. Secretary of State Mike Pompeo lied in recent statements about the presence of members of Hezbollah and in Venezuela, 'it is totally false, ' he said.
"I want to see how many military officers are willing to commit crimes against humanity by not allowing the lives of the most vulnerable to be saved, 250,000 to 300,000 are at risk of dying if they do not receive immediate attention", Guaido said during a gathering of university students.
The US, Canada, numerous Latin American countries and the major European powers all consider Maduro's May 2018 re-election victory to be tainted by fraud and have recognised Guaido, the speaker of the opposition-controlled National Assembly, as Interim President.
Maduro on Wednesday hit back at a tweet by USA national security adviser John Bolton that said "any Venezuelan senior military officer that stands for democracy and recognizes the constitutional government of President Juan Guaido" would not face United States sanctions.
Political tensions in Venezuela between the government and opposition groups came to a head after Maduro was sworn in to a new term on January 10.
In response, Maduro announced he was severing "diplomatic and political" ties with the US, ordering all the USA diplomatic and consular personnel to leave the country in 72 hours.
But the aid blockade could lead to troops disobeying Maduro's orders and allowing the much-needed aid to pass. "You're deaf... They've taken extremist positions".
Maduro, who last weekend rejected an European Union ultimatum to organise snap presidential elections, fumed: "You don't listen to the truth in Venezuela".
He did welcome the Contact Group's proposal to send a mission to Venezuela, though.
On Friday, the Supreme Court asked the attorney general's office to investigate alleged "criminal" conduct by Guaido and the legislature over the "usurpation of functions" that correspond to Maduro.