CÚCUTA, Colombia — The Trump Administration and the Venezuelan opposition have staked their plans to weaken President Nicolás Maduro on a climactic moment only days away: on Saturday, they will try to break his blockade of the border with a delivery of food and medication.
The two have set Feb. 23 as the deadline for an ambitious land-and-sea campaign that would bring humanitarian supplies through Colombia, Brazil and the Caribbean and into the hands of thousands of Venezuelans who have suffered the greatest economic collapse the region has faced in generations.
On Monday, President Trump himself planned to make the case at a rally in Florida. There he was expected to ask Venezuela’s military to break ranks with Mr. Maduro and to call for the immediate delivery of shipments of American supplies, which have been piling up on Venezuela’s border with Colombia for days.
Mr. Trump’s move followed a whirlwind of high-profile visits to the border by American officials — including Senator Marco Rubio of Florida and the head of the United States Agency for International Development — who have embraced the opposition’s plans to use aid as their chief political weapon.
If Mr. Maduro’s stranglehold on the food and medicine supply can be broken, and he can be shown to have lost control of the border, his legitimacy as the country’s president will weaken, the reasoning goes. If the military can be convinced to not stand between the Venezuelan population and the humanitarian aid, he may fall.
“Food and medicine will reach the people of Venezuela and so will liberty and democracy,” said Mr. Rubio, standing in front of the Tienditas Bridge in Cúcuta, which Mr. Maduro’s government blocked with a couple of shipping containers.
It is a risky gamble for Mr. Maduro’s adversaries, who say they are unclear as to how they will break the blockade at the border on Saturday.
While the United States and other countries have embraced Juan Guaidó, the leader of Venezuela’s opposition, as the country’s rightful president, the White House is facing the reality that Mr. Maduro still controls the military, and with it, the state.
“If the opposition — and Trump administration — are trying to find ways to peel away military support for Maduro, threatening its monopoly on food distribution is not likely to be helpful in that regard,” said Cynthia J. Arnson, the Latin America director at the Woodrow Wilson International Center for Scholars.
She added that by creating a political showdown over the humanitarian shipment, the White House only increased the prospects that Mr. Maduro would keep blocking the aid.
For Mr. Guaidó, there is an additional risk: In accepting wholeheartedly Mr. Trump’s embrace, Mr. Guaidó risks looking like a puppet of the United States.
“Being associated too closely with the U.S. carries too much baggage anywhere in Latin America,” said Adam Isacson of the Washington Office on Latin America, a human rights group. “And when you have a leftist government that rallies its base on these issues of American imperialism, it plays closely into their narrative.”
Mr. Isacson, who directs the group’s security and defense program, also expressed concern about the tension that the rhetoric of Mr. Trump and Mr. Maduro was raising on the border.
“With this kind of saber-rattling you create potential for a hair-trigger moment,” he said, citing Mr. Maduro’s dispatch of troops to the border. “An incident there could go badly.”
Cúcuta, which is across a river from Venezuela, now offers the kind of contradictory scenes that reflect a country where two men claim the presidency. One of the shipping containers blocking the bridge into Venezuela, emblazoned with the word “paz,” Spanish for “peace.”
On the Venezuelan side, the government has amassed soldiers, militiamen, armored vehicles and even missiles. On the Colombian side sit news camera crews and trucks full of supplies. Richard Branson, the British billionaire, has invited a lineup of Latin American musicians to perform an aid concert on Friday night.
Yet no one knows how the aid will reach Venezuela. The opposition has so far been quiet about details of its plans, saying that if they released information Mr. Maduro would stymie them with his security forces.
But Gaby Arellano, an opposition lawmaker sent by Mr. Guaidó to coordinate the aid, said that the opposition did not necessarily have to use the blocked Tienditas Bridge.
“The border with Colombia is immensely long, and so is the border with Brazil, and the border with the Antilles,” she said. “We want the aid to be coming in at all points.”
For more than a week, activists and officials have said they are mulling the option of simply smuggling in aid through Venezuela’s porous land borders, along routes long used to transport contraband products and fuel. Opposition activists have said they have already joined forces with the Pemones indigenous community in eastern Venezuela to bring in supplies by river, using their canoes.
Another option, pushed by those looking for a more direct confrontation with Mr. Maduro, would have activists circle an aid truck in Colombia as it slowly makes its approach to Venezuela. Under this plan, protesters from Venezuela would overrun soldiers stationed on the Venezuelan side and allow the aid to move in, possibly using a forklift to push aside the containers blocking the bridge.
In Curacao, opposition officials were buoyed by the willingness of the country’s foreign minister to stage aid along a sea corridor long used by Venezuelan migrants to flee the country. But in recent days, plans appeared to be falling apart as politicians in Curacao objected to the use of the aid as a political weapon.
The uncertainty has left some in Venezuela not counting on aid anytime soon.
“They say they are in charge of the government, but the ones who are in charge are the ones who control the bridge,” said Héctor Cárdenas, 52, who crossed the border to buys a month’s worth of cooking oil, vegetables, soap and medicines in Colombia. “The opposition has no real power.”