Marsh Ireland was only one of the three dominant insurance brokers to respond to an attack from Quinn Direct Insurance, claiming it did not place business insurance with the Irish company because its capacity to meet its liabilities was not measured by an international rating agent.

There was no response yesterday from the internationally-owned groups AON or from Coyle Hamilton Willis to claims from Quinn Direct that they and Marsh were in a "cosy club" to carve up the business market for international insurers such as Allianz, AXA and Aviva.

Quinn Direct claimed the brokers were preventing their clients from receiving the cheapest business insurance premiums in the market by excluding its products from their quotations.

Marsh Ireland's statement was not issued generally and was released to media outlets only if they specifically asked for comment. The company said it was committed to "putting the best interests of its clients first at all times" and said this was the key consideration when designing and placing risk and insurance programmes on their behalf.

The company said it did not place business with Quinn Direct because it does not take out any security rating with international agencies such as Standard & Poors or A&M Best. Akin to the credit rating on a customer looking for a bank loan, such a rating measures the capacity of an insurer to meet its liabilities.

"As part of our commitment to clients, we assess all insurers against certain key criteria. These include not only the products they (the insurers) offer but also their level of security rating," Marsh Ireland said.

"Marsh sources quotes from insurers based in Ireland and abroad who satisfy our minimum security rating requirements. Quinn Direct Insurance does not hold a security rating. Consequently, Marsh Ireland Ltd does not place business with them."

Quinn Direct's spokesman dismissed the statement. "What a surprise? This just reinforces what we've been saying. This proves our point. We don't need to get a credit rating. Loads of other brokers in the country are quite happy to put Quinn Direct to their clients," he said.

"We're quite happy for them if they want to point out to their clients that we do not have this amazing rating but they should still be pointing our prices out to their clients. There are loads of other brokers who are happy to do that."