Moody's Investors Service has placed several ratings on Munich Reinsurance Company under review for possible downgrade.
The specific ratings under review are the company's financial strength rating (Aaa), and the debt (Aa1) and financial strength ratings (Aaa) of its US subsidiary American Re Corporation.
Moody's said the rating action follows Munich Re's announcement on 10 July that it would be increasing reserves at American Re by $2bn.
The rating agency said it would "analyse the financial impact of these actions in the context of Munich Re Group's historically strong capitalisation, stable franchise and conservative fiscal and underwriting management, which have been key considerations in its financial strength ratings".
Moody's concluded that it expects the review to result in the ratings being confirmed at their current levels or being downgraded by one notch.
It added that American Re's ratings, however, could fall by two notches.
