The Trump administration's May 2026 executive order and subsequent September OFAC regulations have expanded secondary sanctions and restricted financial transactions tied to Cuban state energy entities such as CUPET and ENETEC, driving recent enforcement actions including the seizure of multiple biodiesel shipments bound for the island. These steps reinforce the existing embargo framework, which continues to bar U.S. firms from Cuban oil deals despite Cuba's new hydrocarbons law taking effect October 19. Limited U.S. fuel exports to Cuba's private sector have increased, but government-to-government relief remains blocked amid ongoing crackdowns and White House statements confirming no policy shift. Traders assessing near-term sanction relief must weigh these tightening measures against any diplomatic signals from Havana or scheduled bilateral contacts that could alter enforcement priorities.