The tractor trailers were observed on the bridge on Tuesday, Feb. 5.
Bulgaria has joined the majority of European Union countries in recognising Juan Guaidó as interim President of Venezuela.
Shipments were also coming from Venezuelan companies overseas, Colombia, Canada and Germany.
The United States has pledged $20 million in aid that is to be gathered in Colombia, Brazil and an unnamed Caribbean island, but Guaido won't be able to bring it into Venezuela without the military's agreement. Taking a jibe at the US President, he said: "So we have to go through a war to reconsider our relationship and our respect?"
"Here in Venezuela nothing will enter, not one invading soldier", said Maduro, who claims humanitarian aid would be a precursor to a US-led invasion.
Maduro on Monday said he sent Francis a letter seeking his help in fostering dialogue in Venezuela.
Guaido, who declared himself interim president last month, is scheduled to meet later on Tuesday with business leaders at Venezuela's main business group, Fedecamaras, to discuss an economic recovery plan under a future transition government in the OPEC-member South American country.
Trudeau also urged the worldwide community to help Guaido restore democracy and help the economy in Venezuela.
Radev, head of state for the past two years after election on a ticket backed by the opposition and pro-Moscow Bulgarian Socialist Party, said that there is a real risk of escalation and violence in Venezuela, and it was critical to maintain dialogue between the government and the opposition.
Labour leader Jeremy Corbyn - a long-standing admirer of Nicholas Maduro's socialist predecessor Hugo Chavez - has strongly condemned outside interference in Venezuela "whether from the United States or anywhere else".
The Europeans gave Mr Maduro (56) an eight-day deadline to call fresh elections, or else have his authority removed. The group also has managed to get a small amount of aid inside the country, which Graham called "a drop in the bucket" compared to what is needed.
Prime Minister Justin Trudeau and Foreign Affairs Minister Chrystia Freeland branded the Maduro government a dictatorship that has shown an inexcusable disregard for the rule of law and human rights.
The United States could attempt to seek the approval of the United Nations Security Council to deliver aid without Maduro's cooperation, but Russian Federation would likely block such a move.
But Maduro's support in his own region is waning as the countries known as the Lima Group, made up of 13 Western Hemisphere nations, admitted the Guaidó government and Venezuela's National Assembly as full members of that multi-national group.
They also urged Venezuela's military to support opposition leader Juan Guaido as interim president and "not to impede the entry and transit of humanitarian assistance to Venezuelans".
- Pep Guardiola fires message at Liverpool FC ahead of West Ham test
- Pope Francis to hold historic Mass on Arabian Peninsula
- Google Discovered Collecting User Data From Apple Via Internal Apps
- Adam Levine Assures SJWs Their Voices Were Heard During Super Bowl Performance
- Go Vegan, And You Could Win Beyoncé Tickets For Life…
- Australia Has 3 Excellent Reasons to Avoid Floodwaters
- Martial on the bench as Sanchez, Rashford start against Leicester
- Brexit blamed for Nissan's decision to move SUV production to Japan
- Liam Neeson Admits To Rape Revenge Fantasy
- Ryan Fox finishes sixth at Saudi International as Dustin Johnson holds on