The Pentagon announced on Friday it was bolstering US forces in Saudi Arabia following the September 14 drone and missile attack on Saudi oil plants which Washington blames on Iran.
Commenting on the announcement, US Special Representative on Iran Brian Hook said the increase in troops came in response to talks with Saudi Arabia which intensified after "the Iranian attack on Saudi Arabia on September 14."
He said they are part of several tools the US is considering to "reestablish deterrence in the region."
"Saudi Arabia is a longstanding security partner and has requested additional support to supplement their defences and to defend the rule-based international order," Mr Hook said.
The US official reiterated that his government does not seek conflict with Iran but that Washington will defend its troops and interests against any attack from Iran or its proxies.
US Defence Secretary Mark Esper said that two fighter squadrons and additional missile defence batteries were being sent to Saudi Arabia, for a total of about 3,000 new troops from September this year.
The move comes as tensions jumped on Friday after Tehran said that suspected missiles had struck an Iranian tanker in the Red Sea off the coast of Jeddah, Saudi Arabia, setting it on fire.
Tehran did not blame Riyadh for the attack, and US defence officials said they were still looking into it and had no immediate explanation.
Mr Esper said he had spoken with Saudi Crown Prince Mohammad bin Salman Friday to discuss adding US firepower to the Kingdom’s defences against Iranian attacks.
"It is clear that the Iranians are responsible for the recent attacks on Saudi Arabian oil facilities," he said.
"Despite Iran's attempts to deny their involvement, the evidence recovered so far proves that Tehran is responsible for these attacks."
The September 14 attack knocked out two major processing facilities of state oil giant Aramco in Khurais and Abqaiq, roughly halving Saudi Arabia's oil production.
