The Pentagon is preparing a report on who was responsible for the weekend attack on Saudi oil facilities and intends to make it public within 48 hours, a U.S. defense official said.

The official couldn't confirm or deny a CBS News report that the U.S. has identified locations in southern Iran from which it believes more than 20 drones and cruise missiles were launched.

U.S. experts are conducting an intense examination of evidence on the ground in Saudi Arabia and reviewing intelligence such as radar tracks from the region, while the Pentagon's Defense Intelligence Agency is working to pull together a public presentation of declassified material, according to the official.

While Secretary of State Michael Pompeo has asserted that Iran was clearly behind the attack — rejecting the claim of responsibility by Iranian-backed Houthi rebels in Yemen — President Donald Trump has said he is holding off a judgment on who was responsible and what action should be taken in response until he hears more directly from Saudi Arabia.

"Our intelligence community at this very hour is working diligently to review the evidence," Vice President Mike Pence said Tuesday in a speech in Washington.

"I promise you, we're ready," Pence said at the conservative Heritage Foundation. "As the president said, we don't want war with anybody, but the United States is prepared. We're locked and loaded."