McCann vanished from a resort in Praia da Luz, Portugal, where her family was vacationing.

To help find the girl, a team of U.S.-led private investigators has been paid about $1 million. The firm Oakley International was hired to monitor the Madeleine Hotline, carry out detective work and review video footage of possible sightings of the missing girl, the Mail on Sunday reported.

The newspaper reported the company's contract will not be renewed.

British tycoon Brian Kennedy has been underwriting the fund's search for Madeleine. He conducted a review of the company's work on the case.

A source told the newspaper Kennedy was "angry" because he said he believed Oakley's bills of more than $150,000 a month were high.

"There is a sense that they were meaning well but hadn't got as far as they should for the money involved," the unnamed source said. "Brian Kennedy thought their work was far too pricey and wanted to know where the money was being spent. He wasn't satisfied with their answers and the contract was not renewed."