IRAN and the United States each fired barrages of missiles today, as the pattern of tit-for-tat strikes took hold again and hope dimmed for any quick resolution.

After a brief respite, the risk of a return to all-out war emerged once more, with the fighting threatening to engulf even more countries.

Jordan said it had intercepted Iranian missiles on Thursday for the second consecutive day, while Kuwait said a strike in the northern part of the country had killed one person.

Also this week, drones caused fires on ships at an Egyptian port, and Saudi Arabia said it came under fire from Iran-backed militias in Iraq.

The spiralling violence highlighted the difficulty of winding down a five-month illegal and unprovoked conflict launched by the US and Israel on Iran that has sent the price of fuel and other basics soaring, jolted the world economy, and added to concerns about US stockpiles of weapons needed to defend its bases and allies.

But since the US broke the memorandum of understanding agreed by the two sides there has been no public sign of progress.

The Iranian attacks came after the US military said it completed “a heavy wave of strikes against Iran,” conducted in response to an earlier Iranian missile attack on a US base in Jordan.

President Donald Trump vowed to hit Iran “very hard” after it targeted the base.

The military’s Central Command said in a social media post that the US had struck “dozens” of targets belonging to Iran’s Revolutionary Guard, including military command centres as well as missile and drone facilities, and coastal surveillance and defence sites.

Iran’s IRNA news agency said three people were killed and two were wounded in a strike on the island of Qeshm, which lies just off the Iranian mainland in the Strait of Hormuz.

The latest barrage came after the US partnered with Saudi Arabia to strike militias in Iraq, killing at least 20 fighters and six Iranian advisers on Wednesday.

Before the latest eruption, mediators had expressed optimism about bringing Iran and the US back to the negotiating table.

A regional official said on Wednesday that mediators are “still trying with both sides” to restore calm and get an interim agreement to end the war back on track.

Since Iran began threatening and firing on ships in the Strait of Hormuz early in the war, the conflict has wreaked havoc on the global economy as energy shipments through the waterway ground to a near halt.