The relationship has proved lucrative for the Cuban government. Between 40,000 and 50,000 barrels of Venezuelan oil are sent to Cuba daily, despite the fact that Venezuelan oil production has declined more than 60 percent in recent years. Venezuela’s economic subsidy reached its peak at about 12 percent of Cuba’s gross domestic product.

During the boom years, around 90,000 barrels of crude oil daily, representing $9 billion annually, were sent to Cuba. Some estimate that over approximately 15 years, Venezuela has subsidized $35 billion in oil to Cuba.

The country was brought further into debt when Mr. Maduro bought $440 million in foreign crude and sent it to Cuba between 2017 and 2018. The problem, therefore, is not a potential invasion of Venezuela by a foreign power; for over a decade, Cuba has been a parasite, stripping us of our resources.

But unlike Cuba, we are not an island. We have land borders, and our tragedy has spread throughout the region, adding pressure to neighboring countries. To stabilize the region and restore democracy, we must cut off the authoritarian germ rooted in Cuba and Venezuela. Democracy cannot be restored until the two regimes are decoupled.

Mr. Maduro has shown that he will not leave power of his own volition. Those of us who oppose his rule are not armed, nor do we seek to oust his regime violently. We have offered amnesty but it has been rejected. However, we will never accept the normalization of this de facto dictatorship. As long as Mr. Maduro remains in power there will be more deaths, prisoners, persecution and compatriots forced to migrate. The international community has exhausted its diplomatic arsenal because there is no precedent in Latin America for a situation similar to that of Venezuela’s. When it comes, Mr. Maduro’s exit will be equivalent to the fall of the Berlin Wall for the region.

It is a mistake to ask those seeking democracy in Venezuela to distance themselves from their United States and Latin American allies at this juncture. They represent the only opportunity to counterbalance a regime with unlimited power and no institutional oversight, that is armed and willing to exercise violence. Democratic countries must direct pressure toward Havana as well to bring about change in Venezuela.

The call of the National Assembly and the country’s acting president, Juan Guaidó, for Venezuela to stop sending oil to Cuba is a first step. Companies trading with Venezuelan oil must comply if they want to avoid secondary sanctions derived from those already imposed against our state-owned oil and gas company, P.D.V.S.A., by the United States. For its part, the Lima Group must ensure that previously agreed-upon investigations into corruption and human rights violations are carried out, which could involve citizens of its countries, as well as Venezuelans and Cubans.

Finally, the international left wing must understand that Venezuelans are not victims of a single dictatorship, but of two: Mr. Maduro’s and Cuba’s. They must withdraw their solidarity and support for Nicolás Maduro.

Julio Borges was president of the National Assembly of Venezuela and is Juan Guaidó’s ambassador to the Lima Group. This article was translated from the Spanish by Erin Goodman.

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