In a report, Reuters claimed that US President Donald Trump plans to issue an executive order allowing him to impose US sanctions on anyone who violates a conventional arms embargo against Iran.
The sources, who spoke to Reuters News Agency on condition of anonymity, said the executive order was expected to be issued in the coming days and would allow the US President to punish violators with secondary sanctions, depriving them of access to the US market.
The White House did not immediately respond to a request for comment.
The order comes in advance of next month's expiry of a United Nations arms embargo on Iran.
Under the 2015 nuclear deal that Iran struck with six major powers - the United Kingdom, China, France, Germany, Russia and the US - the UN conventional arms embargo is to set to expire on October 18.
The US, which abandoned that deal in May 2018, claimed it has triggered a "snap back," or resumption, of all UN sanctions on Iran, including the arms embargo, which would take effect at 8pm on Saturday night (00:00 GMT on Sunday).
This is while the other parties to the nuclear deal and most of the UN Security Council have said the US has no right to reimpose the UN sanctions and that the move has no legal effect.
ZZ/PR