AM Best has upgraded the financial strength rating of QBE UK to "A" (excellent) from "A-" (excellent) and the issuer credit rating to "a" from "a-".
The outlook for both ratings is stable.
AM Best also announced that it has upgraded QBE International.
In a statement the ratings agency said: "The rating upgrades factor implicit support and the additional financial flexibility afforded by QBE UK's ultimate parent QBE Insurance Group."
It added that it expected QBE UK's strong risk-adjusted capitalisation to improve by year-end 2005.
“The improvement is expected to arise largely as a result of a 30% reduction in net premium income following the transfer in 2005 of QBE UK's participation in the Ensign commercial motor portfolio to its parent company, QBE International Insurance,” AM Best said.