McLachlan departs Herbert Smith for NZ

The move by Campbell McLachlan is regarded as a significant loss because of his contributions to a field that has a shortage of legal expertise.

The New Zealander's impressive list of cases include acting for the government of Chile in the Pinochet affair, Carnival, in its hostile takeover bid for P&O Princess, and stockbrokers in the Maxwell pension fraud.

The running of the international law practice will be split between Robert Volterra, who will head its public side, and Adam Johnson on the private side. They are assisted by eight fee-earners. The department is currently advising, alongside Clifford Chance, on the establishment of an international financial centre in Dubai.

Jeremy Carver, head of Clifford Chance's international law group, described McLachlan as having "taken on the previous international law mantle held by Lawrence Collins QC," who is now a High Court judge. He added: "He has been a great asset to London."

After retiring from the partnership next March, McLachlan will combine working as a consultant at Herbert Smith, which he says he is "very loyal" to, with being chair of international law at Victoria University, New Zealand. He is also stepping down from his post as joint secretary of the British branch of the International Law Association.