US President Barack Obama talks to tourists and Cubans on his arrival at the Havana Cathedral on March 20, 2016
Havana (AFP) - Barack Obama holds rare talks with his Cuban counterpart Raul Castro in Havana Monday, with the US president under pressure to show his policy of engagement can bring change to the communist-ruled island.
On the second day of a historic trip, Obama will visit the seat of the Cuban government on Revolution Square, which sits under the gaze of a vast mural of communist icon Che Guevara.
Obama's visit to Cuba, the first by a US president in 88 years, has raised hopes among battling Cubans that decades of economic and political stasis may be coming to an end.
But the detention of dozens of pro-democracy protestors Sunday and the deployment of a horde of secret police around Old Havana have served as a stark reminder of the regime's iron grip on power.
On the eve of the Castro-Obama meeting, White House officials were locked in talks with their Cuban counterparts to ensure the two leaders take even a few questions from the press.
Obama's administration is betting that opening Cuba's economy will be a bridgehead leading to political change.
But that has left him open to criticism that he has failed to secure immediate democratic change in return for a high profile presidential visit.
Arriving in Havana, Obama admitted change is not going to happen "overnight."
"Change is going to happen here and I think that Raul Castro understands that," he told ABC.
"Although we still have significant differences around human rights and individual liberties inside of Cuba, we felt that coming now would maximize our ability to prompt more change."
Obama will be keen to hear from Castro about economic and political changes that are likely to come from a key Communist Party congress in April.
Castro may be interested to hear how Obama's policy of engagement can weather a turbulent election year and change of administration next January.
- 'Transcendental' change -
The meeting is only the third formal encounter between Obama and the brother of Fidel Castro, who handed over the presidency in 2008.
At stake is the historic shift to end the Cold War conflict, which has seen Washington try to bring Cuba to its knees through an economic embargo, while Havana, a close Soviet ally, became enemy territory.
The trip has been touted mostly for its huge symbolic value, and comes more than a year after Obama and Castro surprised the world in December 2014 by announcing that their countries would begin normalizing relations.
"The presence of a US president on the island for the first time since the 1959 revolution marks a transcendental change in relations between the US and Cuba," Michael Shifter, head of the Inter-American Dialogue think tank in Washington, said.
But some tough issues are up for discussion.
Although the embargo can only be lifted by Congress, where Republicans are far less keen on rapprochement, the Obama administration is chipping away at the edges of the sanctions.
For example, a trickle of US visitors over recent years is soon expected to turn into a flood with the lifting of an onerous requirement that they go to Cuba as part of pre-approved groups.
"I don't think Obama's visit will have an immediate impact on Cuban politics, much less on the near-term decisions of the regime," Shifter said.
"Full normalization will take a lot of time and will be a complex process. To advance, the US Congress needs to go further in lifting the embargo and Cuba needs to speed up its political and economic opening and improve its human rights."
- Baseball diplomacy -
On Tuesday, Obama will meet with a few human rights activists. He will also give a speech -- the main set piece of his trip -- that will be carried live on Cuban television, an unprecedented concession from the authorities.
He will round off the trip by attending a baseball game between the Cuban national team and Major League Baseball's Tampa Bay Rays.
Although meant to be a celebration of shared love for the game, the occasion will also highlight yet another cause of tension: the talent drain of Cuban stars attracted by the lure of the big-money US circuit.
In another major piece of Latin American business, US Secretary of State John Kerry, who is traveling with Obama, was due to meet separately Monday with representatives of the Colombian government and the Marxist FARC rebels, according to a Colombian negotiator.
They have been negotiating in Cuba since 2012 to end their more than 50-year war. Both sides have acknowledged that a Wednesday deadline they had set themselves will pass without the signing of a final accord.