Iran has begun enriching a new batch of uranium just days before a UN deadline for Tehran to suspend atomic fuel work or face possible sanctions, the Washington Post reported yesterday.

Inspectors with the International Atomic Energy Agency (IAEA) plan to formally disclose the new enrichment work, as well as additional Iranian nuclear advances, in a report due out on Thursday, the Post quoted unidentified U.S. and European officials as reporting.

The officials said that Iran's new work involved small quantities of uranium being enriched to an extremely low level that could not be used for nuclear weapons, the newspaper reported.

The UN Security Council in July ordered Iran to suspend uranium enrichment -- a process which can produce fuel for civilian reactors or material for nuclear bombs by Aug. 31 and cooperate with inspectors or face consequences.

If Iran complied, U.S. officials said they were prepared to join talks on Iran's nuclear program and the possibility of future cooperation.

The officials also warned that they were determined to impose sanctions against Tehran if it failed to comply, despite reluctance by Russia and other nations to participate.

Iran has vowed not to stop its nuclear activities, which it contends are for generating electricity.

"We've seen no indication that Iran intends to comply with the U.N. Security Council's condition of suspending its nuclear program," said Nicholas Burns, U.S. Undersecretary of State, in a interview with the Post.

"Should it not comply by Thursday, and should the IAEA report confirm Iran's continued efforts to enrich uranium, the U.S. will move to begin sanctions discussion at the United Nations, and we expect a sanctions resolution to be passed," Burns said.