New Orleans ? BP took some of the blame for the Gulf oil disaster in an internal report issued Wednesday, acknowledging among other things that it misinterpreted a key pressure test of the well. But in a possible preview of its legal strategy, it also pointed the finger at its partners on the doomed rig.

The highly technical, 193-page report attributes the worst offshore oil spill in U.S. history and the rig explosion that set it off to a complex chain of failures both human and mechanical. Some of those problems have been made public over the past 4 1/2 months, such as the failure of the blowout preventer to clamp the well shut.

The report is far from the definitive ruling on the cause of the catastrophe. For one thing, government investigators have not yet begun to fully analyze the blowout preventer, which was raised from the bottom of the sea over Labor Day weekend.

But it provides an early look at the company’s probable legal strategy — spreading the blame among itself, rig owner Transocean, and cement contractor Halliburton — as it deals with hundreds of lawsuits, billions of dollars in claims and possible criminal charges in the coming months and years.