Slaughter and May and Skadden Arps Slate Meager & Flom have scored the leading roles on New York-listed insurer XL Group's $4.1bn (£2.7bn) acquisition of Lloyd's of London rival Catlin Group.

The deal, which requires approval from Catlin's shareholders, is expected to close midway through the year.

Skadden is advising XL alongside financial advisers Morgan Stanley and Goldman Sachs, with a team including New York M&A partner Todd Freed and London corporate partner Scott Hopkins and Robert Stirling. Stirling was formerly head of insurance at Freshfields Bruckhaus Deringer before joining Skadden last month.

Slaughters is acting for Catlin, fielding corporate partners Martin Hatterall and Simon Nicholls, head of financial regulation Jan Putnis, tax partner Steve Edge, pensions partner Jonathan Fenn and head of competition Philippe Chappatte. JP Morgan Chase, Barclays and Evercore are providing financial advice.

Skadden previously acted for XL on its $570m (£376m) sale of subsidiary XL Life Reinsurance to Bermuda-based GreyCastle Holdings in June last year, with Freed also leading the team.

Catlin has owned and managed the largest syndicate at Lloyd's since 2000. It has a network of offices in more than 50 cities, staffing more than 2,300 employees in 25 countries.