Iranian President Hassan Rouhani says progress has been made in negotiations with world powers over Iran's nuclear program and that a final nuclear accord is possible.

In comments published by the official IRNA news agency and the presidential website, Rouhani paints an optimistic picture. He says the progress made in the latest round of talks can be the basis of a final deal. Rohani warns that some significant differences remain, but adds there is nothing that can not be resolved.

Iran and the six-nation group of global powers — the U.S., Russia, China, Britain, France and Germany — hope to reach a rough deal on Iran's disputed nuclear program by the end of March and a final agreement by June 30. Iran has called for a single-stage final accord soon.