WASHINGTON?The top U.S. diplomat in Cuba said Thursday that Cubans eager for political change are rallying behind a grass-roots movement to force a referendum on whether free speech and other rights should be permitted.

Career diplomat Vicki Huddleston said the movement is changing the political dynamic in Cuba, which has been under one-party rule for decades.

She said Cuban dissidents are attempting to take advantage of a provision in the 1976 constitution that permits a referendum if 10,000 signatures are collected.

The petition movement is guided by Oswaldo Paya, a longtime Cuban dissident.

The referendum would ask voters whether they think guarantees of free speech and association are needed and whether they support amnesty for political prisoners.

It would also call for new electoral laws and opportunities for private businesses in Cuba.