Bermudian-based Maiden Holdings and its subsidiaries were yesterday upgraded by ratings agency AM Best.

The financial strength rating went up from A- to A.

The firm’s issuer credit ratings from a- to a for Maiden Reinsurance Ltd and its reinsured affiliate Maiden Reinsurance North America — together known as Maiden Re.

The issuer credit rating for Maiden Holdings and its subsidiary Maiden Holdings North America Ltd rose from bbb- to bbb.

AM Best said: “The ratings upgrades reflect Maiden Re’s consistently profitable underwriting and operating performance within its niche market segments.

“Returns have improved in recent years as the company’s growing book of business has generated results in line with historical levels and as Maiden Holdings has successfully lowered its financial costs.”

But the agency added: “Partially offsetting these positive rating factors is the continued execution risk Maiden Holdings faces in achieving its business plans given the continuing competitive environment in its core reinsurance markets and its client concentration as the AmTrust International Insurance business accounted for approximately 70 per cent of the group’s 2015 total net premiums written.”