McDermott Will & Emery, Sidley Austin and Jenner & Block have taken the lead advisory roles on Singapore-based agricultural business Olam's $1.3bn (£830m) acquisition of Archer Daniels Midland's (ADM) global cocoa operations.

The deal, which is set for regulatory approval and clearances, will make Olam one of the largest suppliers of sustainable cocoa, and the third largest cocoa processer.

McDermott led for Olam, fielding a 16-partner team led by London-based corporate partner Nicholas Azis and international corporate advisory head David Goldman in New York.

Boston-based partner Michael Sartor also led negotiations, with additional support from lawyers in the US firm's Washington DC, Chicago, Brussels, Duesseldorf and Los Angeles offices.

The firm has previously worked with Olam on a number of acquisitions in recent years, including the sale of the company's milk business in Cote D'Ivoire to Netherlands-based FrieslandCampina.

Jenner & Block acted for ADM, with Chicago M&A partner Mercedes Hill and corporate chair Joe Gromacki taking the lead transactional role, and Sidley Austin litigation partner Bill Baumgartner also brought in to advise on competition aspects.

Last year, Illinois-headquartered ADM appointed Kellogg's European legal chief Orla Muldoon as general counsel responsible for Europe, the Middle East and Africa (EMEA).

JP Morgan is acting as financial adviser to Olam.