"It is not uncommon to strike out with offshore wells, and four out of five are dry," Repsol spokesman Kristian Rix said.
The British Broadcasting Corp. reported Saturday that for now Cuba's oil needs are set. It produces half the oil in needs and relies on a trade-off with Venezuela for the rest of it's petroleum needs.
However, it is estimated that Cuban waters could hold deposits of 5 billion to 20 billion barrels of oil.
So the exploratory drilling will continue.
"Today we have strong relations with Venezuela and that's good for Cuba. But if this relationship did not work in the future, that would be a very dramatic position," said Juan Triana, of the Center for the Study of the Cuban Economy.