Iran's response to an incentives package aimed at defusing a dispute over its nuclear program is unacceptable, making the prospect of new sanctions more likely, U.S. officials said Tuesday.

The officials told The Associated Press that a one-page document that Iran presented to European Union foreign policy chief Javier Solana is not a definitive reply to the offer from major world powers but rather a restatement of Tehran's earlier insistence on the right to conduct peaceful nuclear activities.

More>>>