The shortfall is set to last from Feb 10 through March 11, according to a Notice to Aviation (NOTAM) published late on Sunday, and comes just two days after top officials said air travel would not be impacted by a fuel rationing plan announced on Friday.

Cuba has historically relied on Venezuela to provide much of its jet fuel, but the Caribbean island nation has not received any crude or refined products from its top ally since mid-December, when the U.S. moved to block the South American nation’s exports.

US president Donald Trump has since vowed Cuba would receive no more oil from Venezuela and has threatened to slap tariffs on any nation sending fuel to Cuba, effectively cutting off the island’s supply of aviation gas.

Such shortfalls are not new to Cuba and many airlines already have plans in place to deal with them.

A similar crisis last year, as well as others recently, have prompted many carriers to refuel in nearby third countries, including Panama, the Bahamas, the Dominican Republic and the US.

Most airline flights into Havana appeared on time and on schedule on Monday morning.

An early morning COPA airlines flight to Panama departed on time Monday, and several American Airlines flights were slated to arrive later in the day, airport officials confirmed to Reuters.

None of the major carriers servicing Cuba have yet commented on the situation.