The Kremlin said on Monday that the fuel situation in Cuba, which has unveiled a plan to protect essential services and ration fuel, was critical and that U.S. attempts to "suffocate" the island's economy were causing many difficulties.

Cuba detailed its plans to navigate the deepening crisis on Friday as the communist-run government dug in its heels in defiance of a U.S. effort to cut off oil supply to the Caribbean island after declaring Cuba "an unusual and extraordinary threat" to U.S. national security.

"The situation in Cuba is indeed critical. We are aware of this. We are maintaining intensive contacts with our Cuban friends through diplomatic and other channels," Kremlin spokesman Dmitry Peskov told reporters.

Russia is trying to restore its own battered ties with the United States as President Donald Trump seeks to broker a deal to end its war in Ukraine. But the Kremlin made clear it was unhappy with Washington's treatment of Cuba.

"The suffocating tactics employed by the United States are indeed causing many difficulties for the country. We are discussing with our Cuban friends possible ways to resolve these problems, or at least to provide all possible assistance," said Peskov.

He was answering a question about reported jet fuel shortages and whether that might affect Russian tourists wanting to leave Cuba, a longtime ally of Moscow's. Russia's ambassador to Cuba, Viktor Coronelli, told the state RIA news agency last week that Moscow had repeatedly supplied oil to Cuba in recent years, and would continue to do so.