Let's TalkZapaday, Verrijn Stuartlaan 7, Rijswijk, Netherlands.
The US deadline for Iran to start cooperating with the International Atomic Energy Agency's (IAEA) investigation into its nuclear program, expires. Should Tehran not meet the deadline, the issue will be referred to the UN security Council.
"If by March Iran has not begun substantive cooperation with the IAEA, the United States will work with other board members to pursue appropriate board action, and would urge the board to consider reporting this lack of progress to the U.N. Security Council," said US diplomat Robert Wood.
"Iran cannot be allowed to indefinitely ignore its obligations ... Iran must act now, in substance," he added.
The US, Israel and the EU suspect Iran has been using its uranium enrichment program to develop nuclear weapons. Iran has, however, denied the allegations and denounced the Western sanctions on its economy.
The growing US frustration at a lack of progress in the IAEA's inquiry into possible military dimensions to Iran's nuclear program coincides with recent reports on evidence that the country is enriching growing amounts of uranium in an underground bunker.
The latest round of talks between Iran and the IAEA has been scheduled for December 2012.
The Islamic country was first reported to the UN Security Council over its nuclear program by the UN nuclear agency's 35-nation board in 2006.