(WASHINGTON) — So what does the United States have to do in order to officially establish an embassy somewhere?

Not much more than change the sign on the door, even in Cuba.

There are few legal requirements for a U.S. mission or other diplomatic building to become an embassy. Countries just have to exchange letters or notes saying they want to establish ties. And in this case, the United States has to end its agreement with the Swiss government, which has protected U.S. officials in Cuba for 53 years.

“That will be done as soon as possible, whereupon we would transition to becoming an embassy and we would change the sign on our mission,” U.S. Assistant Secretary of State for Western Hemisphere affairs Roberta Jacobson said Thursday.

But just because establishing an embassy is so casual doesn’t mean it will happen quickly. All the changes that go into normalizing relations, like expanding travel licenses, take a while to be implemented and put in the Federal Register.

So Americans looking to get their first legal Cohibas back to the states will still have to wait a few weeks.

“Days or weeks, certainly not months,” Jacobson said.

Once that happens, the building and personnel are already there. Jacobson noted that the United States already has more officials in Cuba than many other countries that have full relations with Havana, and the United States Interest Section there — built in 1953 by the U.S. firm Harrison & Abramovitz and now led by career foreign service offer Jeffrey DeLaurentis — regularly hosts Thanksgiving dinners, Fourth of July parties and other events.

But while the building and the people are already there, it will still be a while until an ambassador calls the new embassy home. There has to be an official embassy before an ambassador can be appointed, and then the waiting game for Senate confirmation, which has sometimes taken more than a year recently, begins.

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