MEXICO CITY — It had become a political sticking point: As long as Cuba remained on the American government’s list of states that sponsor terrorism, there would be no historic opening of America’s first full-fledged embassy in Havana in more than 50 years.

President Obama’s decision, announced on Tuesday, to take Cuba off the list unclogs the process of restoring diplomatic relations between the countries and removes a much-resented stigma that has kept foreign banks and investors away. It also opens the way for the poor island to access multilateral loans.

But while the change in designation will make it easier for non-American companies to do business with Cuba, in practical terms, it goes only a short way to reconnecting American businesses, experts said.

American companies hoping to export televisions or cars to Cuba, or build hotels there, still face the tangle of sanctions that make up the United States trade embargo — a complex scaffold of statutes, regulations and executive orders that only Congress can eliminate.