WASHINGTON – The United States and allies argued about whether Iran is stepping up threats against American forces in the Middle East – or responding to threats from the Trump administration.

U.S. officials told The New York Times they escalated their warnings to Iran because of intelligence showing photographs of missiles loaded onto small boats in the Persian Gulf.

"Overhead imagery showed fully assembled missiles, stoking fears that the Islamic Revolutionary Guards Corps would fire them at United States naval ships," The Times reported.

The Times noted that Europeans and some congressional lawmakers said "Iran’s moves might mostly be defensive against what Tehran believes are provocative acts by Washington."

Last week, CNN reported that Iran loaded ballistic missiles on boats.

The United States warned Iran not to attack U.S. forces and sent B-52 bombers to the Persian Gulf to counter alleged threats. Wednesday, the State Department ordered nonemergency U.S. employees out of Iraq because of the tensions.

This week, U.S. and British officials engaged in a public dispute over whether Iran is more of a threat than it has been.

British Maj. Gen. Christopher Ghika, the No. 2 officer in the U.S.-led coalition fighting the Islamic State, also known as ISIS, in Syria and Iraq, said Tuesday that the threat from Iran is no greater than it was months ago.

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The Pentagon pushed back.

Navy Capt. Bill Urban, a spokesman for U.S. Central Command, said Ghika was wrong and his comments "run counter to the identified credible threats available to intelligence from U.S. and allies regarding Iranian-backed forces in the region."

Lawmakers fear the tensions could lead to military conflict.

Democrats have been particularly critical of national security adviser John Bolton, who has made no secret of his desire to seek regime change in Iran.

“We should do everything possible to prevent an unnecessary war, beginning with immediately reopening diplomatic channels and toning down the rhetoric," said Sen. Dianne Feinstein, D-Calif.

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Trump played down the potential for military action, saying he would respond only to some kind of attack from Iran.

Asked about a Times report that Bolton and other officials discussed the deployment of 120,000 troops to the region to contain Iran, Trump said, "Hopefully, we're not going to have to plan for that. And if we did that, we'd send a hell of a lot more troops than that."