Iran defies US threat

President Hassan Rouhani yesterday vowed that Iran would boost its missile capabilities despite warnings from Washington that it is ready to ditch a landmark nuclear deal over the issue.

His comments came as Iran displayed a new missile at a military parade marking the anniversary of the outbreak of its devastating 1980-1988 war with Saddam Hussein's Iraq.

"Whether you like it or not, we are going to strengthen our military capabilities which are necessary for deterrence," Rouhani said in a speech broadcast live on state television.

"We will strengthen not only our missiles but also our air, land and sea forces... When it comes to defending our country, we will ask nobody for their permission."

Iran has said repeatedly that it has no choice but to boost its defences as its regional rivals Israel and Saudi Arabia sign huge arms contracts with Washington and other Western governments.

Criticism by the Donald Trump administration of a 2015 nuclear deal between Iran and major powers, including the United States, has focused heavily on Tehran's continuing missile programme.

Tehran says that the missiles are entirely legitimate under the terms of the deal as they are not designed to carry a nuclear warhead.

But Washington says they breach the spirit of the agreement as they have the potential to carry a nuclear warhead and has imposed new sanctions over Tehran's continuing launches and tests.

Iran says all of its missiles are designed to carry conventional warheads only and has limited their range to a maximum of 2,000 kilometres, although commanders say they have the technology to go further.

That makes them only medium-range but still sufficient to reach Israel or US bases in the Gulf.

Thus far, the UN nuclear watchdog and the US State Department have reported that Tehran has complied with the terms of the nuclear deal.

But Trump, who this week described the deal as an "embarrassment", is due to report to the US Congress on October 15 on whether or not he believes that Iran is in compliance.

If, as now appears increasingly likely, he decides that it is not, it could open the way for renewed US sanctions and perhaps the collapse of the agreement.

Trump said on Wednesday he had made his decision but was not yet ready to reveal it.

Washington has been particularly concerned about Iran's heavy intervention in Syria on the side of the government of President Bashar al-Assad and its support for Shiite rebels in Yemen who control the capital in defiance of its Saudi-backed government.

But Rouhani ruled out any change of policy in the region.

"Whether you like it or not, we are going to defend the oppressed peoples of Yemen, Palestine and Syria," he said.