Axa, Allianz and Aviva groups are among 15 insurers that Standard & Poors (S&P) have warned face a downgrade in their credit rating.
The credit rating agency said that for European insurance groups it could lower their current ratings by one notch.
It added that the negative watch was due to "the aggregate effects of exposure to eurozone sovereign debt, related bank debt and deposits, the resulting potential impact on capital adequacy, and the impact of the expected slowdown in economic activity in the eurozone."
S&P also noted that the rating actions will, in their turn, affect certain holding companies' "core and strategically important" operating subsidiaries.
The move follows its decision on 5 December to place 15 of the 17 eurozone member countries on a negative watch.
For domestic insurers based in Ireland, Portugal, Spain and Italy including Allianz Plc, RSA Insurance Ireland, Axa Insurance and Aviva Insurance (Europe) SE, along with Millenniumbcp-Ageas Group the downside risk for their ratings was revealed as being two notches.
S&P noted that it expected to resolve the negative watches within four weeks of resolving the negative watches on the relevant sovereign debts.
This piece originally appeared in Cover's sister title, Insurance Age.
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