Trump asked for options for attacking Iran last week but held off, report says

Incumbent US president Donald Trump asked for options on attacking Iran's main nuclear site last week but ultimately decided against taking the dramatic step, a source has said.

Trump made the request during a meeting on Thursday with his top national security aides, including Vice President Mike Pence, his new Acting Defence Secretary Christopher Miller, and General Mark Milley, chairman of the Joint Chiefs of Staff, Reuters reported the official as saying.

The report further said advisors persuaded Trump to not go ahead with a strike because of the risk of a broader conflict.

His request for options came a day after a UN atomic watchdog report showed that Iran had finished moving a first cascade of advanced centrifuges from an above-ground plant at its main uranium enrichment site to an underground one, in a fresh breach of its nuclear deal with big powers.

Trump has spent his tenure engaging in an aggressive policy against Iran, withdrawing from the Iran nuclear deal negotiated by his Democratic predecessor, Barack Obama, and imposing economic sanctions against a wide variety of Iranian targets.

Trump, who has challenged the results of the November 3 presidential election in courts, is to hand over power to Democratic President-elect Joe Biden on January 20.

In January, Trump ordered a US drone strike that killed Iranian military General Qassem Soleimani at the Baghdad airport. A full-blown strike on Iran's main nuclear site at Natanz could flare into a regional conflict and pose a serious foreign policy challenge for Biden.

Iran's 2.4 tonne stock of low-enriched uranium is now far above the deal's 202.8 kg limit. It produced 337.5 kg in the quarter, less than the more than 500 kg recorded in the previous two quarters by the International Atomic Energy Agency.