The criticism is contained in a resolution to be put up for passage by vote or consensus Thursday at a meeting of the 35-nation board of the International Atomic Energy Agency.
The resolution urging Iran to stop activities that could be used to make a bomb cannot be enforced. But it is significant in seeking to show world-power resolve on engaging Iran at a time of increased Israeli warnings that time is running out for diplomacy.
Iran denies any interest in nuclear arms. The diplomats demanded anonymity because they were not allowed to discuss confidential information.