Washington, Sep 20 (IANS/EFE) Lawyers for a US government subcontractor serving a 15-year sentence in Cuba on a conviction for subversion argued here Friday before a federal appellate court that their client should be allowed to sue the US.

Alan Gross, now 65, and wife Judith sued Development Alternatives Inc(DAI) and the US Agency for International Development(USAID) in 2012 for failing to inform him in advance about the risks of the Cuba mission and for refusing to pull him out after he expressed concerns.

While the couple reached a settlement with DAI in 2013, a US district court threw out their suit against USAID.

Gross' attorneys challenged the dismissal Friday before a three-judge panel of the US Court of Appeals for the District of Columbia.

The three judges heard the arguments from both sides and adjourned without indicating when they would rule on the appeal.

The district court judge who dismissed the suit against USAID said the federal government enjoys immunity for injuries suffered abroad.

USAID contracted Maryland-based DAI for a project to expand Internet access and the flow of information in Cuba.

DAI hired Gross to travel to the island, where he was detained in December 2009 with satellite communications equipment he was planning to distribute among Cuba's Jewish community.