NEW YORK (Bloomberg) — A trade group representing corporate insurance buyers said brokers including Marsh & McLennan Cos. and Aon Corp. should reject a new type of incentive pay being proposed by insurers including Chubb Corp. and Travelers Cos.The fees proposed by Chubb and Travelers are essentially the same as the payments Marsh, Aon and their biggest rivals banned during an investigation by New York's attorney general in 2004, said Terry Fleming, a director of Risk and Insurance Management Society Inc. A statement from the group on Wednesday made no distinction.

"We are disappointed to learn that some brokers are apparently reconsidering their pledge to refuse to accept these fees," said RIMS, which represents 83 percent of Fortune 500 companies. "For brokers and independent agents to accept these fees in transactions that are made on behalf of the buyer represents an inherent conflict of interest."

Marsh & McLennan, Aon and Willis Group Holdings Ltd., the world's three biggest insurance brokers, banned so-called "contingent commissions" in 2004, giving up more than $1 billion in annual revenue to settle conflict-of-interest probes by Eliot Spitzer, New York's attorney general at the time. Spitzer said the undisclosed fees were tantamount to kickbacks, encouraging brokers to steer business to the most lucrative insurers.

New York-based Marsh & McLennan is still weighing whether to accept some form of the new payments, and Chicago-based Aon, which said they were under review last month, had no immediate comment today. Willis, based in London, said last month it wouldn't accept them.