RIYADH – US Democratic Senator Chris Murphy said on Tuesday that the Pentagon blocked him from visiting a key military base in Qatar during his Middle East visit, accusing the White House of hiding the costs and implications of its war on Iran.

Murphy told reporters in Riyadh, the second stop on a congressional delegation trip to Qatar and Saudi Arabia, that he was denied a visit to Al Udeid Air Base.

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"This trip confirmed for me that there is an active, unprecedented, unconstitutional effort underway to hide the costs of this war and the implications of this war from Congress and the American people," he said.

Al Udeid Air Base is the largest US base in the region and has been repeatedly attacked by Iran since the war began in late February.

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Many other members of Congress have also criticized the Pentagon over its lack of transparency about the cost, strategy and casualties of the war, which has dragged on for more than seven months.

Asked for comment, a senior Pentagon official said Murphy's office was informed before the trip that he would not receive the department's support to access the base, in line with Defense Secretary Pete Hegseth's March directive restricting travel to the region.