Donald Trump. Picture: REUTERS
Donald Trump. Picture: REUTERS

Washington/Bengaluru — US President Donald Trump on Sunday warned Iranian President Hassan Rouhani not to threaten the US again, after Rouhani cautioned Trump about pursuing hostile policies against Tehran.

"Never, ever threaten the United States again or you will suffer consequences the likes of which few throughout history have ever suffered before," Trump said in a Twitter post.

Rouhani said on Sunday that "war with Iran is the mother of all wars", but did not rule out peace between the two countries.

"We are no longer a country that will stand for your demented words of violence & death," Trump tweeted. "Be cautious!"

Rouhani warned the US on Sunday not to threaten Iran’s oil exports, and suggested Iran had alternatives to the Strait of Hormuz.

US Secretary of State Mike Pompeo, meanwhile, launched a rhetorical assault on Iran’s leaders on Sunday, comparing them to a "mafia" and promising unspecified backing for Iranians unhappy with their government.

Pompeo, in a California speech to a largely Iranian-American audience, dismissed Rouhani and Foreign Minister Javad Zarif, who negotiated a nuclear deal with the US and five other countries, as "merely polished front men for the ayatollahs’ international con artistry".

Trump withdrew in May from the 2015 nuclear accord designed to stop Iran from developing nuclear weapons.

Tehran has said its nuclear work is just for electricity generation and other peaceful projects.

Iran "is run by something that resembles the mafia more than a government", Pompeo said, citing what he called Iranian leaders’ vast wealth and corruption.

Pompeo’s speech was the latest step in a communications offensive launched by the Trump administration that is meant to foment unrest in Iran and help pressure its government to end its nuclear programme and support of militant groups, US officials familiar with the matter said.

The offensive is meant to work in concert with severe economic sanctions that Washington plans to resume in the coming months, including on Tehran’s oil exports, its principal revenue generator.

Publicly, the Trump administration says its policy with Iran is not "regime change", but to change Tehran’s behaviour so it stops nuclear and missile work, support for proxies in the Middle East, and backing of militant groups.

The US would work with countries that import Iranian oil "to get imports as close to zero as possible" by November 4, Pompeo said.

"While it is ultimately up to the Iranian people to determine the direction of their country, the US will support the long-ignored voice of the Iranian people," he said.