Relations might be warming between the U.S. and Cuba, but President Barack Obama's move on Wednesday was ice cold.

The U.S. leader renewed a 20-year-old state of national emergency to continue to administer the blockade against the Caribbean island, at the same time as planning a trip there within weeks to take talks over normalizing diplomatic ties to the next stage.

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Obama’s Proclamation 9398 prolongs the financially crippling blockade begun under President Bill Clinton in 1996, using emergency powers sanctioned by Congress.

It bans ships and planes from the U.S. from entering Cuban waters or airspace without government permission, and requires the president to annually renew these emergency powers.

There is one revision to Obama’s blockade action, USA Today reports, in that the Coast Guard are only allowed to inspect and seize vessels believed to have violated the blockade "to the extent consistent with international law.”

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And the rhetoric of the document has also mellowed, replacing aggressive language and expressing a wish for "a peaceful, prosperous and democratic Cuba.

According to the United Nations, the U.S. blockade has cost Cuba US$117 billion.

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