BP wants a federal judge to order restitution — plus interest — of what it says are hundreds of millions of dollars in overpayments to some businesses that claimed losses due to the 2010 Gulf oil spill.

In a Friday court filing, BP points to a revised policy for calculating losses that was approved by a U.S. federal court in May.

The company says the court should order recalculation of awards paid prior to that change.

Meanwhile, BP continues its legal fight on a related issue: whether businesses have to prove they were directly harmed by the spill to collect money. A district court and an appeals court have ruled that, under the settlement BP agreed to, proof of direct harm isn't needed. BP has said it plans a Supreme Court appeal in the U.S. on that issue.

While it has been unsuccessful so far on the causation issue, it did succeed in getting the method for calculating losses changed after arguing that the administrator of settlement claims wasn't correctly matching business's revenues and expenses. For instance, it cited a claim by a company that purchased inventory in early 2009 that wasn't sold until months later. The claim, BP said, gave a false impression of inflated profits in those later months.

"BP has consistently and publicly maintained that it would be entitled to recover overpayments once the misinterpretation was corrected," BP spokesman Geoff Morrell said in an emailed statement. Letting the awards stand would be unfair to other claimants whose awards were calculated at a different time, he said.

Plaintiffs' attorneys had a different view.

"This is just another attempt by BP to back out of the commitment it made to the Gulf. BP itself has already told the Supreme Court that it `will have no practical way of recovering' the money it paid," said an emailed statement from attorneys Steve Herman and Jim Roy.

"Every claim that was paid was done so according to an independent trust agreement that BP co-authored and agreed to."

The Deepwater Horizon rig at BP's Macondo well off the Louisiana coast blew out in April 2010, killing 11 workers and spewing oil into the Gulf for nearly three months.

A settlement of business economic loss claims following the spill was hailed both sides when it reached in 2012, but BP later said the claims administrator was misinterpreting the agreement, leading to the disputes over what caused damages and how payments should be calculated.