The report on Iran nuclear program is expected to confirm that Iran continues uranium enrichment activities.

The report, prepared by U.N. nuclear watchdog Mohamed ElBaradei, head of the Vienna-based ernational Atomic Energy Agency, could trigger tougher U.N. Security Council sanctions against Tehran.

the report will be sent to the agency's 35-nation board and to the Security Council.

The council set a 60-day deadline on Dec. 23 for such a freeze and said continued Iranian defiance past that ultimatum, which runs out Wednesday, could lead to sanctions additional to those it imposed last month.

Top Iranian officials showed no signs of compromise and has rejected the Security Council resolution as "illegal," saying it would not give up its right to enrich under the Nuclear Nonproliferation Treaty.

"The enemy is making a big mistake if it thinks it can thwart the will of the Iranian nation to achieve the peaceful use of nuclear technology," Iranian state TV's Web site quoted President Mahmoud Ahmadinejad as saying Wednesday.