The US has launched a barrage of airstrikes against Iran, prompting Iranian retaliation on Jordan and Bahrain on Wednesday.
The strikes followed a weekend exchange of fire, the first since July, and attacks on Monday on two tankers leaving the Strait of Hormuz, the global oil supply waterway that Iran has effectively closed to shipping.
The US military's Central Command (CENTCOM) said it had completed a wave of strikes against IRGC targets on Tuesday, including air defense sites, radar systems, maritime assets and facilities, mine-laying capabilities, and communications sites.
Trump warned Iran against responding to Tuesday's assault, threatening to strike again "at a much harder and higher level".
Iran struck back across the Middle East region early on Wednesday.
Jordan's armed forces said its air defense systems dealt with 13 ballistic missiles that entered the kingdom's airspace, 10 of which were intercepted and three fell in remote areas. Bahrain said Iranian drones were intercepted and destroyed.
Meanwhile, Kuwaiti Armed Forces announced that its air defences are actively engaging with missile and drone threats.
Since the US and Israel attacked Iran on February 28, Iran has responded with missile and drone strikes on US allies in the region.
The six-month-old conflict had shifted into an economic standoff before the weekend strikes, in which US forces attacked Iran's Larak Island on Sunday, and Iran responded by launching missiles at two US air bases in Jordan.
In an interview with Fox News, Trump played down the prospects of another ceasefire. The US and Iran reached a deal in June that quickly fell apart, largely over interpretations of Iranian control of the Strait of Hormuz.
"I think an agreement with them isn't worth the paper it's written on. We gave them a lot of chances," Trump told Fox News.

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