Sirius International Insurance Company has had its rating increased by Moody's to "positive" from "stable" after producing profitable growth in a competitive environment in 2000.
Until 2000, traditional reinsurance represented most of its business. But finite reinsurance and financial risks, most through subsidiary Scandinavian Re, accounted for 60% of its income last year.
However, while Sirius has an improved underwriting performance, it still has a comparatively weak brand and franchise in a mature but changing industry. There is also concern that the majority non-traditional reinsurance business could make income volatile.
Moody's added: "A major obstacle for Sirius will be a continued expansion without allowing the quality of business to concurrently deteriorate."