(Reuters) - A group led by the head of the United States' biggest science organization is in Cuba this week to discuss ways to rekindle scientific cooperation as U.S.-Cuba relations slowly improve under U.S. President Barack Obama.

Nobel Prize-winning scientist Peter Agre, president of the American Association for the Advancement of Science (AAAS), told Reuters on Wednesday the group had met with government officials and Cuban scientists, all of them enthusiastic about doing science together.

"Nothing concrete so far, but much good will," he said on the second day of a visit that ends on Friday.

The Cubans "are nothing other than warm-hearted about this. They would love to see things move forward," said Agre, who won a Nobel Prize in chemistry in 2003.

He said U.S. and Cuban scientists had a long history of working together that continued even after relations between their governments soured following the 1959 revolution that put Fidel Castro in power.

But the last five decades of hostilities, and particularly the years under Obama predecessor George W. Bush, have made joint efforts difficult. The AAAS hopes this will change under Obama.

"Cuba has been kind of a dead zone (for cooperation) because of the separation, but the opportunity to be here is something I'm looking forward to," Agre said. "It's something we would both benefit from."

The AAAS last sent a delegation to Cuba 12 years ago, he said.

The best opportunities for cooperative research appear to lie in medicine, where Cuba's emphasis on public health and vaccine development could prove valuable to the United States, and the environment, particularly shared resources such as the Gulf of Mexico and migratory wildlife, he and delegation members said.

As a start, Agre said, the AAAS will invite several senior Cuban scientists to its annual meeting in February in San Diego.

Obama has said he wants to end hostilities with Cuba, but also that he will maintain the 47-year-old U.S. trade embargo against the communist-led island until the Cuban government makes progress on human rights. Cuba has said human rights are strictly an internal matter not subject to negotiation.

Obama has slightly eased the embargo by allowing Cuban Americans to freely visit and send money to their homeland.

"These types of delegations provide an opportunity to start building the scaffolding of a relationship, which science has done throughout the history of international relations," said Agre delegation member Patrick Doherty, director of the U.S.-Cuba Policy Initiative for the Washington-based New America Foundation think tank.