President Obama to Visit Cuba in Historic Trip Next Month

— -- President Obama is planning a trip to Cuba in March, marking the first time in more than 80 years a sitting U.S. president will visit the country, according to sources with knowledge of the plan.

The president officially announced his trip via Twitter on Thursday morning.

In a post detailing the trip on Medium, Deputy National Security Adviser Ben Rhodes said the president is traveling to Cuba to press for more reforms, noting that while advancements have been made, "still, this progress is insufficient."

"There is much more that can be done -- by the United States, and by the Cuban government -- to advance this opening in ways that will be good for Cubans, and good for the United States. That is why President Obama is traveling to Cuba," Rhodes wrote. "We want to open up more opportunities for U.S. businesses and travelers to engage with Cuba, and we want the Cuban government to open up more opportunities for its people to benefit from that engagement."

The trip is planned for March 21-22 before the president flies to Argentina on March 23-24. During the trip to Cuba, President Obama is set to meet with Cuban President Raul Castro. The two men first met face-to-face during a summit in Panama last year.

First Lady Michelle Obama will travel with the president to Cuba, and the First Family will join him in Argentina.

The move comes roughly 15 months following the president's pledge with Raul Castro to reopen diplomatic channels following a prisoner exchange and the humanitarian release of U.S. contractor Alan Gross in December 2014.

Since the announcement, the two countries have had a series of diplomatic talks, leading to the reopening of embassies last summer and the recent deal restoring commercial air traffic.

The last and only sitting U.S. president to visit the island nation only 90 miles south of the Florida keys was Calvin Coolidge, in 1928, to address the Sixth Annual International Conference of American States in Havana.

He met with Cuba's President Gerardo Machado, who was in office from 1925 to 1933, until he was forced into exile.

President Jimmy Carter traveled to Cuba in 2002, 20 years after leaving office, at the invitation of President Fidel Castro.

Carter also made a trip in 2011.

This is a developing story. Please check back in for updates.