Iran said today that it had successfully tested a new medium-range missile in defiance of warnings from Washington.
State television aired footage of the launch of the Khoramshahr missile, which was first displayed at a high-profile military parade in Tehran yesterday.
Iran's Revolutionary Guard unveiled its latest ballistic missile at a military parade, which also carried in-flight video from the nose cone.
The timing of the test was not disclosed by the broadcaster, although officials had said yesterday that it would be tested "soon".
Previous Iranian missile launches had resulted in US sanctions and accusations of violation of the spirit of the 2015 nuclear deal between Tehran and major western powers.
President Donald Trump has threatened to junk the agreement over the issue, saying that Iran's missile programme could give it the technical knowhow for a delivery system for a nuclear warhead with the expiration of a sunset clause in the deal in 2025.
Trump will report to Congress on 15 October on whether he believes Iran was in compliance of the agreement and whether it remains in the US' interests to stick by it.
According to commentators, if Trump were to decide it was not, it could open the way for US lawmakers to reimpose sanctions, leading to the potential collapse of the agreement.
According to commentators, the action comes as a direct challenge to president Donald Trump, who in August signed a bill imposing mandatory penalties on those involved in Iran's ballistic missile programme and anyone who did business with the them. This is the first time that the Khoramshahr, with a range of 2,000 kilometers (1,250 miles), has been displayed in public.
Trump has, on several occasions, vowed to take a tougher line toward Iran than his predecessor, and threatened to renegotiate or even dismantle the nuclear deal, and shoot Iranian boats out of the water if they provoke US naval vessels in the Persian Gulf.