Slaughter and May has reaffirmed its ties with Abbey, advising the bank on the £3.6bn sale this month of its life assurance business.

The firm has taken the lead role advising Abbey on the deal despite earlier fears it would lose the bank as a client after its £8.5bn takeover by Spanish banking giant Santander Central Hispano in 2004. The deal, which was announced on 8 June, sees the FTSE 100-listed UK bank offload its onshore and offshore life businesses as well as part of its asset management business to London-based financial services group Resolution.

The disposal features a portfolio of brands that includes Scottish Mutual Assurance, Scottish Provident and Abbey National Life.

Corporate partner Mark Bennett led the team for Slaughters with assistance from fellow corporate partners Simon Robinson and Robert Chaplin and regulatory partner Charles Harvey-Kelly.

Bennett told Legal Week: "There is the possibility of a reshuffle of advisers when there is a change of holding company like that, but we have had long links with Abbey."

Herbert Smith also scored a major mandate on the deal, advising Resolution, with corporate partners Geoffrey Maddock and Michael Shaw taking the lead roles.

Resolution has previously been advised by Slaughters, which acted for the closed life insurance fund operator on its £850m acquisition of Royal & Sun Alliance's UK life operations.