In a series of tweets, the US president warned leaders in Tehran against following through on their threats to avenge the death of Soleimani, who was killed by a US airstrike on Thursday.
He said: “Iran is talking very boldly about targeting certain USA assets as revenge for our ridding the world of their terrorist leader who had just killed an American, & badly wounded many others, not to mention all of the people he had killed over his lifetime, including recently hundreds of Iranian protesters.
“He was already attacking our Embassy, and preparing for additional hits in other locations. Iran has been nothing but problems for many years.
“Let this serve as a WARNING that if Iran strikes any Americans, or American assets, we have targeted 52 Iranian sites (representing the 52 American hostages taken by Iran many years ago), some at a very high level & important to Iran & the Iranian culture, and those targets, and Iran itself, WILL BE HIT VERY FAST AND VERY HARD. The USA wants no more threats!”
Mr Trump sent a formal notification to congress under the War Powers Act on Saturday of the drone strike that killed the head of Iran’s elite Quds force, General Qassem Soleimani.
The notification, required by law within 48 hours of the introduction of American forces into an armed conflict or a situation that could lead to war, has to be signed and sent to congress.
It comes after the US president ordered a drone strike on Mr Soleimani which killed him and several others near Baghdad’s international airport.
Iran has vowed a “harsh vengeance” in retaliation to the assassination.
Ben Wallace, the defence secretary, has urged “all parties” to de-escalate the situation – although he said the US was “entitled to defend itself”.
After speaking to his US counterpart Mark Esper, Mr Wallace said American forces have been “repeatedly attacked by Iranian-backed militia” in Iraq during “the last few months”.
He said: “General Soleimani has been at the heart of the use of proxies to undermine neighbouring sovereign nations and target Iran’s enemies.
“Under international law the United States is entitled to defend itself against those posing an imminent threat to their citizens.”
Royal Navy warships HMS Montrose and HMS Defender have been deployed to the Strait of Hormuz in the Gulf to guide British-flagged vessels through the key oil passage.
The defence secretary said the government “will take all necessary steps to protect our ships and citizens at this time”.
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