Associated Press

HAVANA – Jimmy Carter visited a major biotechnology lab with Fidel Castro on Monday, just one week after U.S. officials accused Cuba of trying to develop
biological weapons – a charge the Cuban leader has denounced as a lie.

Carter, the first U.S. head of state in or out of office to visit Cuba since Castro's 1959 revolution, also met with two leading Cuban dissidents Monday for a briefing on
human rights. The opposition leaders called on Carter to promoted dialogue between the two countries.

Traveling with his wife and a small group of executives and staff from his Carter Center, the former American president had no biotechnology experts in his delegation
for the visit to the Center of Genetic Engineering and Biotechnology on the outskirts of Havana. Carter has a science background, but in nuclear technology.

Elizardo Sanchez and Oswaldo Paya, who saw Carter at his hotel, are both coordinators of Project Varela, a proposed referendum asking voters if they want guarantees of individual freedoms, an amnesty for political prisoners, the right to own their business and electoral reforms.

Paya said the men explained the need for dialogue. "Carter understands the concept very well because he is a man of dialogue."

In Washington, a White House spokesman said Monday that Castro should give his own people the same freedom to travel and speak to dissidents that he has given Carter.

"Why have one standard for a visitor and have a far worse, much more repressive standard for his own people?" Ari Fleischer said.

Carter, who did more than any other president to ease tensions with Cuba, arrived Sunday to the strains of "The Star-Spangled Banner." Castro turned to his visitor and said, "It's been a long time since that happened."

Carter's visit comes after the latest in many moments of U.S.-Cuban tension. Last week Undersecretary of State John Bolton said Cuba sought to develop biological weapons.

On Friday, Cuba denounced the claims as "lies," challenged the United States for evidence and promised Carter "complete access" to any Cuban biotechnology laboratory.

Sunday night, a dark-suited Castro threw a dinner for Carter and his delegation at the Palace of the Revolution. The visit gave the Cuban leader a chance to reach out to
Americans, and he used it by symbolically throwing open the doors of the island to Carter.

Castro said a Carter speech on Tuesday would be broadcast live. "You can express yourself freely whether or not we agree with part of what you say or with
everything you say," Castro said. "You will have free access to every place you want to go."

"We shall not take offense at any contact you may wish to make," he added, an obvious reference to the dissidents and human rights activists Carter plans to meet.

Cuban officials have been irritated with some other foreign leaders who have held similar meetings, but Castro said Carter had proved his sincerity in the past.

"A man who, in the middle of the Cold War and from the depth of an ocean of prejudice, misinformation and distrust ... dared to try to improve relations between both
countries deserves respect."

Speaking in Spanish, Carter said he hoped "to discuss ideals that Rosalynn and I hold dear ... peace, human rights, democracy and the alleviation of suffering."

Carter, the first former or sitting president to visit Cuba since Calvin Coolidge came in 1928, has emphasized that this is a private trip and that he will not be negotiating
with the Cuban government.

There have been 10 American presidents since Castro took power, and relations were less hostile under Carter than any other.

As president, Carter oversaw the re-establishment of diplomatic exchanges between the two countries and negotiated the release of thousands of political prisoners. He
also made it possible for Cuban exiles to visit relatives on the island and, for a short time, for other Americans to travel here freely.

But relations have remained cold. A U.S. trade embargo is still in place and visits by Americans are tightly limited, or are supposed to be: tens of thousands skirt or ignore
the travel ban each year.