Apollo Global Management (APO) and KKR (KKR) are facing increased scrutiny from US insurance regulators over fast-growing multi-asset securitization structures that officials say could pose transparency and "circular ownership" risks, the Financial Times reported Friday.

Documents from the National Association of Insurance Commissioners raised concerns about interconnectedness and opaque exposures in the investment structures, with regulators considering stricter disclosure requirements and capital rules, according to the report.

The review includes Apollo's Multi-Asset Prime Securities and certain KKR-sponsored investment vehicles, the report said. Apollo told the Financial Times that its products are transparent and have been reviewed by regulators.

Apollo Global Management and KKR did not respond to MT Newswires' request for comment.

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