Talks between the head of the United Nations nuclear agency and high-ranking Iranian officials to discuss Iran's nuclear program have been canceled.

International Atomic Energy Agency head Mohammed ElBaradei had been expected to meet in Vienna Monday with the Iranian officials.

However, the talks were called off after a meeting earlier Monday between Iranian deputy negotiator Javad Vaidi and EU negotiator Robert Cooper made little progress.

The U.N. Security Council has imposed two rounds of limited sanctions on Iran for its refusal to suspend uranium enrichment, which can be used to create nuclear weapons or for producing energy.

In a meeting with the IAEA's board of governors Monday, ElBaradei said Iran continues to expand its uranium enrichment program without UN inspectors making any progress to determine "the nature and scope" of the program.

The United States and its allies accuse Iran of trying to develop nuclear weapons. Tehran says its program is for peaceful, civilian use.