A rebuke of Iran led by the U.S. and its close allies at the global nuclear watchdog agency has drawn a vow by the Islamic republic to further ramp up uranium enrichment.

The Islamic Republic has begun to activate its modern centrifuges. This is allegedly a response to the decision of the International Atomic Energy Agency's Board of Governors regarding the country's peaceful nuclear program,

Iran has defied international demands to rein in its nuclear program and has increased its stockpile of uranium enriched to near weapons-grade levels, according to a confidential report by the United Nations’ nuclear watchdog seen Tuesday by The Associated Press.