NEW YORK -- The U.S. government contractor jailed in Cuba for bringing satellite phones to Jewish groups claims he was unaware that he was carrying equipment financed by the United States, a former top aide to President Jimmy Carter said Thursday.

Former National Security Adviser Robert Pastor, who served as the White House’s point man on Cuba, accompanied Carter on his trip to Havana this week. The former president met with both the Castro brothers as well as Alan Gross, an American development worker who was sentenced to 15 years in prison after getting caught smuggling sat phones, which he claimed were to provide Internet to Jewish groups.

“We did meet with Gross. He claims not to know he was bringing equipment from the U.S. government,” Pastor told a Cuban conference audience at the Bildner Center for Western Hemisphere Studies at the City University of New York. “The facts are simply not all that clear, and this is coming from someone who has spoken to all sides of this, often.”

Carter also met with Jewish group leaders, who claimed they knew nothing about Gross or his phones, said Pastor, now a professor at American University in Washington.

Gross’ trial was closed to the media, and Pastor’s comments marked the first time anyone indicated that the long-time development worker — considered a “mercenary” by the Cuban government — was unaware of the nature of his work. Pressed for details after his speech, Pastor said he regretted “getting into that level of detail.”

“I did not speak to him. I do not feel authorized to say what he said,” Pastor said in an interview.

Gross, Pastor said, hopefully will not serve as long a term in prison as the “Cuban Five” intelligence agents imprisoned in the United States — 13 years.

“A case could be made that a humanitarian gesture after 13 years in prison should be seriously considered” by the Obama administration, he said. He added that both Havana and Washington made it clear they were not interested in a prisoner swap.

Havana is worried about “future Alan Grosses” as the Obama administration has not scrapped the U.S. Agency for International Development program that funded his trip.

Gross’ wife Judy and the company that sent him, Development Alternatives Inc., could not be reached for comment late Thursday.

Carter, his wife Rosalynn and his retinue spent nearly six hours — including dinner — with the 79-year-old Raúl Castro, who replaced brother Fidel, at first temporarily and then officially, after Fidel suffered a nearly fatal health crisis in 2006.

“He is secure in his position and aware of his age and limited time to undertake reforms that he’s now convinced are needed to improve the economy,’’ Pastor said.

The reforms include a significant expansion of private businesses, profound cuts in government subsidies and other measures expected to be taken up at a congress of the ruling Communist Party that starts April 16.

Pastor is too optimistic because Castro will never surrender his political controls or his anti-Washington bent, said Jaime Suchlicki, head of the Institute for Cuban and Cuban-American Studies at the University of Miami.

“Yes he’s undertaking limited reforms, but he’s not going to dismantle communism or create a capitalist society,’’ Suchlicki said. “There will be no political opening and his government will remain repressive and anti-American.”