The two former Cold War adversaries have progressed in opening relations since Obama and Cuban President Raul Castro announced in December 2014 that they intended to restore ties. Both have reopened embassies in the other's capital and announced plans this week to restore flight service between the nations.
Yet that progress is "insufficient," Obama said, which is why he will travel in person.
"We still have differences with the Cuban government that I will raise directly. America will always stand for human rights around the world," Obama wrote.
Obama will press Castro on human rights and meet with other Cubans as well, deputy national security advisor Ben Rhodes said. The two leaders last met on the sidelines of the Summit of the Americas in Panama in April.
"Yes, we have a complicated and difficult history. But we need not be defined by it," Rhodes wrote.
Noting that the U.S.-Cuba rapprochement also has boosted relations with other Latin American nations, Rhodes said that immediately following Obama's trip to Cuba, he will visit Argentina in hopes of beginning "a new chapter of improved relations" there as well.
Obama's visit will come in the heat of a contentious presidential campaign back in the U.S., and just a week after the Florida primary.
Republican candidates condemned the announcement. Former Florida Gov. Jeb Bush called it a "tragedy" that Obama would legitimize the Castro regime.
Florida Sen. Marco Rubio, the son of Cuban immigrants, said during a town hall Wednesday that Cuba's government is "as oppressive as ever," and criticized the administration for failing to press its leaders for more democratic reforms.
For more White House coverage, follow @mikememoli