US to hit Iran with 'major' new sanctions Monday: Trump

President Donald Trump said Saturday that the United States would impose "major" new sanctions on Iran in two days -- a move sure to exacerbate tensions with the Islamic republic inflamed by the downing of a US spy plane.

President Donald Trump speaks during a meeting with Canadian Prime Minister Justin Trudeau in the Oval Office of the White House, Thursday, June 20, 2019, in Washington. Trump declared Thursday that "Iran made a very big mistake" in shooting down a U.S. drone. [Photo: IC]

Trump tamped down the threat of military action on Friday, when he called off retaliatory strikes at the last minute because the response was not "proportionate" to the drone's destruction over the Strait of Hormuz.

But he had said military action is still an option and brandished the threat of sanctions ever since.

Now, he has set a timetable for fresh punitive economic measures to heap more pressure on an Iranian economy already reeling from the sanctions in place since Trump withdrew from an international nuclear deal with Tehran.

"We are putting major additional Sanctions on Iran on Monday," Trump tweeted.

"I look forward to the day that Sanctions come off Iran, and they become a productive and prosperous nation again - The sooner the better!"

Earlier, before heading to Camp David for meetings with his advisors on the situation, Trump said he would be Iran's "best friend" and that the Islamic republic could be a "wealthy" country if it renounced nuclear weapons.

"We're not going to have Iran have a nuclear weapon," Trump told reporters outside the White House.

"When they agree to that, they're going to have a wealthy country. They're going to be so happy, and I'm going to be their best friend. I hope that happens."

"Let's make Iran great again," he added, tweaking for the occasion his main domestic political mantra.

Last year, Trump withdrew the United States from the deal designed to curb Iran's nuclear ambitions in exchange for sanctions relief, and reinstated measures designed to choke off Iranian oil sales and cripple its economy.

As part of the spike in tensions, the US has beefed up its military presence in the Middle East and blamed Iran for attacks on oil tankers on the Gulf of Oman. Iran denies any responsibility.

"Everyone was saying I'm a war-monger, and now they say I'm a dove," Trump said Saturday as he was peppered with questions about the Iran drama.

"I think I am neither, if you want to know the truth. I'm a man with common sense, and that's what we need in this country, is common sense."

Trump insisted it is up to the Iranian leadership how the current crisis plays out.

"If the leadership of Iran behaves badly, then it's going to be a very, very bad day for them," he said.

"But hopefully they're smart and hopefully they really care for their people and not themselves, and hopefully we can get Iran back on to an economic track that's fantastic, where they're a really wealthy nation, which would be a wonderful thing," he added.