The United States is dispatching roughly 9,000 troops aboard warships to the Middle East as President Donald Trump weighs new strikes against Iran, a US official told the Associated Press on Thursday.

The deployment includes the USS Theodore Roosevelt carrier strike group with the cruiser USS Chosin, and the USS Makin Island amphibious ready group with the landing ships USS John P. Murtha and USS Anchorage. Over 7,000 sailors and 2,000 Marines are involved.

The move could bring three US carriers to the region, joining the USS George H.W. Bush and USS George Washington, an unusually high naval presence. The Wall Street Journal separately reported the deployment at 9,000 to 10,000 personnel.

Trump also said early indications linked Iran to a co-pilot who tried to crash an Israel-bound FlyDubai flight on Wednesday, warning of retaliation. “They’ll be hit, very hard, don’t worry,” he said, offering no details.

The forces could arrive in the region by the end of October, according to the official. Oil markets reacted on Thursday, with Brent crude rising 4.4 per cent to $102.31 a barrel, according to CNBC.