Capping off a historic trip to Cuba, President Obama spoke directly to the Cuban people on Tuesday, promising to open up a new relationship with the country and bury decades of turmoil.

“I am here to bury the last remnants of the Cold War in the Americas,” Obama said in an address. “I am here to extend a hand of friendship to the Cuban people.”

The changes he is seeking include the United States lifting the 54-year-old trade embargo with Cuba, but a change in how the Cuban government deals with human rights abuses.

“The differences between our governments over these many years are real, and they are important,” Obama said. “I’m sure President Castro would say the same thing. I know because I’ve heard him address those differences at length.”

Cuban President Raúl Castro watched the address from a balcony inside a theatre where Obama spoke. The address comes just a day after Obama had a sit-down meeting with Castro, held an hour-long news conference and stood for an official portrait with the Cuban president.

Obama also stressed the importance of opening up markets in the country and allowing the Cuban people more economic freedom. He told Castro not to “fear” freedom of speech and dissent from Cuban citizens, something that has overshadowed the trip.

As Obama arrived, the Cuban government reportedly arrested dozens of anti-Cuban government protesters. Castro denied in his news conference that Cuba holds any political prisoners while telling members of the media he would release any if they provided a list.

Change in the United States seems unlikely, at least in the short term, as Republicans controlling Congress have expressed doubt about opening up a relationship with a country they say is still controlled by an authoritarian government.

“It is a big deal,” said Steffen Schmidt, university professor of political science. “When a policy does not work for 55 years and when it actually reinforced and strengthened the Cuban regime, because Castro blamed everything on the U.S., you should not keep that policy.”

Schmidt said to expect a growth in relationships, corporate contracts, travelers and even growing support from Cuban Americans who are skeptical about the new relationship.

Obama attended a Major League Baseball exhibition game later Tuesday before departing Cuba for Argentina with the first family.

Obama also commented on the terrorist attack in Brussels that killed at least 30 people and injured another 170.

“The thoughts and the prayers of the American people are with the people of Belgium,” Obama said. “We stand in solidarity with them in condemning these outrageous attacks against innocent people. We will do whatever is necessary to support our friend and ally, Belgium, in bringing to justice those who are responsible. And this is yet another reminder that the world must unite, we must be together, regardless of nationality, or race, or faith, in fighting against the scourge of terrorism. We can — and will — defeat those who threaten the safety and security of people all around the world.”