Cuba has announced that international airlines will no longer be able to refuel at its airports due to a shortage of aviation fuel. This development comes in the wake of U.S. President Donald Trump’s threats to impose tariffs on any nation that provides oil to Cuba.

On Sunday, Cuban officials stated that the country would deplete its aviation fuel reserves by Monday, potentially causing significant disruptions for airlines. According to the EFE news agency, which cited two sources, this kerosene shortage is anticipated to last for at least a month, affecting all international airports across Cuba.

Efforts to reach Cuba’s Foreign Ministry and the Cuban Embassy in London for comments were unsuccessful, as they did not immediately respond to CNBC’s request.

Since January 3, the Trump administration has intensified its pressure on Cuba, following a bold military operation aiming to unseat Venezuelan President Nicolás Maduro, a steadfast ally of the Cuban government.

Trump, in an executive order issued at the end of January, said the Cuban government constituted “an unusual and extraordinary threat,” which required a national emergency declaration.

The U.S. president said that Cuba’s ties to countries including China, Russia and Iran, human rights violations and communist leadership destabilize the region “through migration and violence.”

As part of the announcement, Trump said U.S. tariffs may target countries that provides any oil to Cuba, whether directly or indirectly.

Gripped by a deepening energy crisis, Cuba on Friday outlined extensive measures designed to protect essential services and ration fuel supplies for key sectors.

The plan reportedly includes restrictions on fuel sales, the closure of some tourist establishments, shortening school days, and a reduction of the working week in state-owned companies to four days, from Monday to Thursday.

Russia, which holds friendly ties with Cuba, said Monday that Havana’s fuel situation was “truly critical” and that U.S. attempts to further pressure the country were causing numerous problems.

“The situation in Cuba is truly critical. We know this. We are in intensive contact with our Cuban friends through diplomatic and other channels. Indeed, let’s say the U.S.’s stranglehold is causing many difficulties for the country,” Kremlin Spokesperson Dmitry Peskov told reporters on Monday, according to state news outlet RIA Novosti.

Cuba’s Foreign Minister Bruno Rodríguez Parrilla previously said the country’s leadership condemned Washington’s tariff threats in the “strongest possible terms.”

In a statement posted on Jan. 30, Parrilla also accused the U.S. government of resorting to “blackmail and coercion in an attempt to make other countries to join its universally condemned blockade policy against Cuba.”

Mexican President Claudia Sheinbaum said last week that her government would aim to send humanitarian aid to Cuba from Monday, adding that the country is working to find a diplomatic solution to resume oil shipments to the Caribbean island.

Mexico had paused shipments of crude and refined products to Cuba amid pressure from the Trump administration.