A damaged U.S. Boeing E-3 Sentry airborne warning and control aircraft following an Iranian strike at Prince Sultan Air Base in Saudi Arabia. (Social media)

Iran has reportedly caused billions of dollars in damage to U.S. military assets and bases in the Gulf region, sparking questions about the Trump administration`s transparency regarding potential costs for repairs.

Six people familiar with the damage said runways, high-end radar systems, dozens of aircraft, warehouses, command headquarters, aircraft hangars and satellite communications infrastructure were struck by Iranian forces in an interview with NBC News.

The destruction spans across several countries in the Middle East and could cost up to $5 billion to repair.

The projected price tag does not include fixes to radar systems, weapons systems, aircraft and other equipment that were either impaired or unsalvageable due to Iranian strikes, the outlet reported.

Initial damage was caused to U.S. base Camp Buehring in Kuwait by an Iranian F-5 fighter jet within the first few days of the war on Feb. 28 when U.S.-Israeli strikes began.

Al Dhafra Air Base and Al Ruwais military base in the United Arab Emirates recorded damage to fuel storage, a medical clinic, hangars and barracks in addition to other warehouses and buildings.

Prince Sultan Air Base in Saudi Arabia; Muwaffaq Salti Air Base in Jordan; and Camp Arifjan, Camp Buehring and Shuaiba Port in Kuwait also saw U.S. resources damaged.

Three officials told NBC News there was later extensive damage to the headquarters building for the U.S. Navy in Bahrain and at least two air defense systems.

Repairs to the U.S. Navy Fifth Fleet headquarters could total $200 million alone, one congressional official told The New York Times following a Pentagon assessment.

An external assessment from American Enterprise Institute (AEI) shows Iranian forces also struck Ali Al Salem Air Base in Kuwait, a runway at Al-Udeid Air Base in Qatar in addition to a munitions storage facility at a military base in northern Iraq, per NBC.

"As part of Epic Fury, the potential future costs to rebuild American military infrastructure overseas may include repair, reconstruction, outright replacement, or even abandonment/decommissioning of locales," Mackenzie Eaglen, a senior fellow at AEI, told the outlet.

"War damage also includes estimated costs for infrastructure that is unsalvageable," she added.

Other damages include at least one fighter jet, a dozen MQ-9 Reaper drones, two MC-130 tankers, helicopters and an E-3 Sentry plane.

The Pentagon did not immediately respond to The Hill`s request for comment.

In March, the Pentagon estimated that the first six days of the war against Iran cost more than $11.3 billion, absent of calculations for needed repairs.

A total of $5.6 billion was spent on munitions during the first two days of the war.

Briefings for lawmakers regarding the cost of combat have been sparse causing pause for elected officials and their staffers.

"No one knows anything. And it`s not for lack of asking," one of the aides told NBC.

"We have been asking for weeks and not getting specifics, even as the Pentagon is asking for a record-high budget," the person added.