New York Daily News and other sources report on the letter:
"Fidel Castro blasts Obama’s trip to Cuba in harsh letter: ‘We don’t need the empire to give us any presents’"
"....In a 1,500-word bristling letter titled "Brother Obama," published Monday in Cuban state media, Castro, who did not meet with Obama during the visit, recounted decades of U.S. aggression against his country and told Obama to stay out of Cuba's affairs."
For full article: http://www.nydailynews.com/news/politics/fidel-castro-blasts-obama-trip-cuba-harsh-letter-article-1.2579926
Here is the letter in English from Cuba's publication, Granma: