CMS Cameron McKenna has scored a lead advisory role opposite elite City firm Slaughter and May as construction company Carillion acquires Alfred McAlpine in a £572m deal.

Camerons corporate partner Gary Green and senior partner Richard Price led the team acting for support services company Alfred McAlpine, assisted by James Parkes and Catherine Beckett.

The instruction represents Camerons' largest deal to date for Alfred McAlpine, having been handed its first corporate instruction for the client – which also uses firms including national giant Pinsent Masons and southwest outfit TLT – over the summer.

The deal also marks the second high-profile takeover Camerons has acted on in the construction sector in recent times, with the firm last year scoring a role advising construction and development client John Laing on its £1bn acquisition by Henderson, which instructed Freshfields Bruckhaus Deringer.

Carillion instructed long-term adviser Slaughters, which fielded a team headed up by corporate partners William Underhill and Kathy Hughes.

The deal creates one of the UK's largest construction and support services companies, with combined annual revenues of £4.7bn, and is expected to generate efficiencies of around £30m by 2009.

Alfred McAlpine had previously agreed a higher bid from Carillion in November but last month accepted a reduced offer amid turbulent market conditions.

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