Bermuda-based Enstar Group (ESGR) has signed definitive agreements with Arden Holdings to acquire Atrium Underwriting Group and Arden Reinsurance Company for approximately $183m and $79.6m respectively.

Enstar CEO Dominic Silvester said, "Our core focus remains on acquiring insurance and reinsurance companies that are in run-off, however we believe Atrium will provide us with a high quality operation at Lloyd’s that includes a skilled underwriting and management team that will help create new opportunities for us to grow and prosper."

An underwriting business at Lloyd’s of London, which manages Syndicate 609, Atrium focuses on accident and health, aviation, marine property, non-marine property, professional liability, property and casualty binding authorities, reinsurance, upstream energy, war and terrorism insurance, cargo and fine art.

A Bermuda-based reinsurance company, Arden Reinsurance provides reinsurance to Atrium and is currently in the process of running off certain other discontinued businesses.

The two transactions are expected to close by the end of 2013 subject to regulatory approvals.

Enstar provides management, consultancy and other services to the insurance and reinsurance industry.