Shearman & Sterling and Sullivan & Cromwell are among a clutch of firms to win advisory roles as European telecoms group Altice agrees to buy US operator Cablevision in a deal worth $17.7bn (£11.4bn).

Shearman is advising longstanding client Altice with a cross border team that includes London M&A partner George Karafotias and Paris capital markets partner Sami Toutounji.

The deal is the latest acquisition by French-Israeli billionaire and Altice founder Patrick Drahi, who has built a telecoms and cable empire in recent years via debt-backed purchases in France, Portugal and Israel.

Covington & Burling, Mayer Brown, Ropes & Gray, De Brauw Blackstone Westbroek and Morris Nichols Arsht & Tunnel are also providing legal advice to Altice.

Ropes' London team is advising Altice on financing arrangements for the acquisition, with City finance partner Michael Kazakevich at the helm.

On the target side Sullivan is advising Cablevision, with a New York team including corporate partners Joseph Frumkin, John Mead and Melissa Sawyer.

Mintz Levin Cohn Glovsky and Popeo and Richards Layton & Finger are also advising Cablevision.

The transaction is expected to close in the first half of next year. 

In May, Mayer Brown, Ropes, Covington & Burling, Latham & Watkins and Paul Hastings all secured mandates on Altice's $9.1bn (£5.8bn) acquisition of US cable company Suddenlink Communications.

In January, Ropes and Latham & Watkins were appointed to advise on Altice's $6bn (£4bn) fundraising round to finance its acquisition of rival telecom company Oi's Portuguese assets.