The combined XL Group and Catlin will gain advantages of scale in a consolidating reinsurance market, XL CEO Mike McGavick has told investors.

XL announced last month it would buy Catlin for $US2.79 billion ($3.51 billion) in a cash and share deal, gaining a significant increase in premium scale to more than $US3 billion ($3.78 billion) of reinsurance net written premium.

The new XL Catlin will become the eighth-largest reinsurer, up from 13th for XL and 19th for Catlin.

The merger will increase distribution through Catlin’s Lloyd’s platform and give the group a stronger Asia-Pacific presence.

Catlin brings gross written premium of $US373 million ($470.02 million) from its Singapore underwriting hub, and both XL and Catlin have offices in Australia.

Mr McGavick will continue as CEO, while Catlin founder Stephen Catlin is expected to become Executive Deputy Chairman of the XL Catlin board.

The group will gain increased relevance with brokers through greater premium volume, product offerings and a wider global network, Mr McGavick says.

Its underwriting mix will shift towards specialty lines and it plans to become a global leader in aerospace, fine art and specie, and political risk and crisis management.