US President Barack Obama was due in Cuba Sunday to bury the hatchet in a more than half-century-long Cold War conflict that turned the communist island and its giant neighbor into bitter enemies.

US President Barack Obama was due in Cuba Sunday to bury the hatchet in a more than half-century-long Cold War conflict that turned the communist island and its giant neighbor into bitter enemies.

Reversing generations of US attempts to cut Cuba from the outside world, Obama, First Lady Michelle Obama and their two daughters will arrive in Havana for a three-day trip.

It won't just be the first visit by a sitting US president since Fidel Castro's guerrillas overthrew the US-backed government of Fulgencio Batista in 1959, but the first since President Calvin Coolidge came 88 years ago.

Obama, seeking to leave a historic foreign policy mark in his final year in office, was due to see old town Havana late Sunday, hold talks with Cuban President Raul Castro on Monday, and attend a baseball game before leaving Tuesday.

Although Obama has already loosened restrictions on US citizens visiting Cuba, the lifting of the decades-old US economic embargo can only be decided by a Republican-dominated Congress that is far less keen on detente with President Raul Castro's Cuba.

The Castro government warned Obama ahead of his arrival that lectures on democracy would be "absolutely off the table."

But White House deputy national security adviser Ben Rhodes insists that the subject will be brought up and that Obama will also meet members of Cuba's beleaguered opposition, "people who've shown great courage in pursuing their rights and pursuing a better future for the Cuban people."

On Tuesday, Obama will give a speech at the National Theater that will be carried live on Cuban television, giving him a unique platform to make his case.