The island's official Granma newspaper reported online Monday that the operation dubbed Bastion 2004 is an effort to keep Cuba prepared in the event of a U.S. invasion.
Tensions between the United States and Cuba were escalated earlier this year, when the Bush administration imposed tougher sanctions on the Caribbean nation, part of the U.S. ongoing policy that's lasted more than 40 years. Part of the policy limits the amount of money that Cuban-Americans can send to relatives in Cuba and the frequency of their visits to Cuba.
Cuba struck back by banning the U.S. dollar from circulation and imposing a lofty tax on changing dollars to Cuban pesos.
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