Cuba and the United States signed an agreement on marine protected areas Wednesday, their first cooperation on the environmental front since a thaw in relations between the former Cold War foes.

Full diplomatic ties were restored between the US and Cuba in July, after more than five decades of often high tensions.

The deal is an unprecedented chance for US and Cuban experts to cooperate on marine protected areas, according to National Oceanic and Atmospheric Administration chief Kathryn Sullivan. She signed the deal with Cuban Science, Technology and Environment deputy minister Fernando Gonzalez.

Though the diplomatic standoff has been called off, it is not all smooth sailing yet for the neighbors across the Florida Straits.

The comprehensive US economic sanctions on Havana largely remain in place, unchanged, because the Republican-run US Congress has yet to vote on lifting them. 

In the meantime, the Americas' only communist state has very little access to credit, other than from allies China or Venezuela.