A U.S. contractor has appealed his 15-year jail sentence in Cuba.

On Friday, Alan Gross told the communist country's Supreme Court he meant Cuba no harm while working on telecommunications equipment. He says he was only trying to improve Internet service for a small Jewish community.

He was detained in late 2009 while working on a secret pro-democracy program funded by the U.S. Agency for International Development aimed at increasing Internet access in Cuba.

Gross was sentenced and sent to prison last March on charges of crimes against Cuba.

The Supreme Court says a final sentence for Gross will be revealed in a couple of days.

Former U.S. president Jimmy Carter met with Gross in March and called on authorities there to release him. Gross's mother and daughter are both suffering from cancer, and there have also been requests to release the contractor on humanitarian grounds.

The United States and Cuba do not have formal diplomatic relations, only interests sections that are technically part of the Swiss embassies in each other's capitals.