The International Atomic Energy Agency is to report on whether Iran has met this deadline. But news agencies report the IAEA will likely say Iran has not only ignored the ultimatum but has expanded the program.
The head of the IAEA, Muhammad el-Baradei, has said Western powers' strategy of telling Iran to halt enrichment as a precondition of talks is out of date.
Instead, el-Baradei has said Western powers should focus on limiting the program so it can't be used to make nuclear weapons.
Such comments by el-Baradei have reportedly upset officials from the United States and some European allies.
Meanwhile today, new French President Nicolas Sarkozy said Iran must cooperate with the international community over its nuclear program or face stricter sanctions.
In his remarks published in the German magazine "Cicero," Sarkozy also joined the United States in objecting to el-Baradei's comments.
According to the Reuters news agency, IAEA ambassadors from the United States, France, Germany, and Britain reportedly plan to complain to el-Baradei this week for what they consider the IAEA chief's "unhelpful remarks."