BP PLC said Monday that it will pay for all the cleanup costs from a massive oil spill in the Gulf of Mexico that could continue spewing crude for at least another week.

The company posted a fact sheet on its Web site saying it took responsibility for the response to the Deepwater Horizon spill and would pay compensation for legitimate claims for property damage, personal injury and commercial losses.

"We are responsible, not for the accident, but we are responsible for the oil and for dealing with it and cleaning the situation up," chief executive Tony Hayward said Monday on ABC's "Good Morning America." He said the equipment that failed on the rig and led to the spill belonged to owner Transocean Ltd., not BP, which operated the rig.

Meanwhile, Hayward said chemical dispersants seem to be having a significant impact keeping oil from flowing to the surface, though he did not elaborate.

The update on the dispersants came as BP was preparing a system never tried nearly a mile under water to siphon away the geyser of crude from a blown-out well a mile underwater. However, the plan to lower 74-ton, concrete-and-metal boxes being built to capture the oil and siphon it to a barge waiting at the surface will need at least another six to eight days to get it in place.