President Barack Obama has the power to further weaken U.S. sanctions against the Communist-run island nation beyond the normalization of relations with Havana that he announced on Wednesday, experts said.

While the restoration of diplomatic ties to Havana after decades of animosity was a big breakthrough, the real obstacle to normal ties between the two countries is the decades-old embargo.

With Republicans due to take control of both the U.S. House of Representatives and the Senate in January, the chance of lawmakers scrapping all sanctions on Cuba soon is almost zero.