The US State Department has recently reduced staffing at several of its embassies across the Middle East.
In a declassified memorandum released on Friday, US Director of National Intelligence Jay Clayton warned that Iran is intensifying efforts to attack US government personnel stationed throughout the Middle East.
The memorandum, addressed to US Secretary of State Marco Rubio, warns of growing dangers facing American personnel in the Middle East.
At the same time, US President Donald Trump is weighing whether to resume military operations against Iran after the November midterm elections.
Clayton wrote in the memorandum: "Intelligence we have obtained through multiple channels shows that Iran has significantly stepped up its attack operations targeting US personnel. Iran's planned lethal attacks against American citizens have entered an advanced stage of operational preparation in the Middle East and certain other countries."
In recent days, the US State Department has reduced staffing at several embassies in the Middle East.
Meanwhile, brewing tensions between the Houthis and Saudi Arabia have further heightened regional tensions.
Clayton added that the intelligence on Iran's plans to attack Americans "involves a broader range of personnel than those currently cleared to receive this information."
He said the Office of the Director of National Intelligence (DNI) will downgrade the classification of the relevant intelligence as much as possible so that it can be more easily shared with those who may be at risk.
Clayton previously served as a federal prosecutor for the Manhattan district of New York.
This summer, after gaining the support of Senate Republicans and completing the appointment confirmation process, he began leading the US intelligence apparatus.
CIA Director John Ratcliffe was also copied on the memorandum.
The memorandum comes as Trump is hinting at a possible escalation of the current war against Iran.
In early October, Trump decided to pause new military strikes against Iran until after the midterm elections.
Now, as the battle for a congressional majority nears its conclusion, he is considering ramping up military action.
Speaking to supporters at a rally in Fort Myers, Florida, on Friday, Trump said: "We might do another little 'Epic Fury.' Or they'll agree to make a deal. If they're smart, they'll just say, 'Let's get down to business.' But I doubt they will, because they may not be smart."
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