Mandel Ngan, AFP | US President Barack Obama shakes hands with Cuba's President Raul Castro on the sidelines of the Summit of the Americas on April 11.

In a small conference room in a Panama City convention center, President Barack Obama and Cuban President Raul Castro sat side by side in a bid to inject fresh momentum into their months-old effort to restore diplomatic ties.

Obama said he wanted to “turn the page” on old divisions, although he acknowledged that significant differences between the governments would remain.

“This is obviously a historic meeting,” he said as the two leaders met on the sidelines of a . “It was my belief it was time to try something new, that it was important for us to engage more directly with the Cuban government.”

“And more importantly, with Cuban people,” the president added. "We are now in a position to move on a path toward the future”.

Castro told the US president he was ready to discuss sensitive issues, including human rights and freedom of the press, maintaining that “everything can be on the table”.

Fidel Castro's brother said he agreed with everything Obama had said – a stunning statement in and of itself for the Cuban leader.

“We are disposed to talk about everything – with patience,” he said in Spanish. “Some things we will agree with, and others we won't.”

Earlier in the day, Castro launched into an exhaustive history of Cuban grievances against the US in his speech to fellow leaders attending the summit.

"I have told President Obama that I get very emotional talking about the revolution," the Cuban leader said, noting that Obama wasn't even born when the US began sanctioning the island nation.

"I apologize to him because President Obama had no responsibility for this," he added, describing his US counterpart as “an ”.

To the applause of hemispheric leaders, Castro drew attention to Obama's modest origins, saying it was the source for his decision to turn a new page in relations with the former Cold War enemy.

Venezuela tensions

Colombian President Juan Manuel Santos summed up the mood, saying "an old obstacle in relations between Latin America and North America is being removed."

Underscoring his increasing engagement with Latin America, Obama said Brazilian President Dilma Rousseff would be visiting Washington in June, two years after she cancelled a scheduled trip over revelations of US spying against her.