Allen & Overy and Simmons & Simmons have taken 48 hours to push through what they claim is the largest ever Asian takeover bid.
Hong Kong's dominant telecommunications operator, Cable & Wireless HKT, has accepted a £22.5bn cash and share offer from local internet start-up company Pacific Century Cyberworks (PCCW).
A&O head of corporate Richard Cranfield and corporate partner Helen Harrison-Hall led the team that advised Cable & Wireless.
Simmons head of corporate finance in London, Stuart Evans, led the team that advised PCCW.
Cranfield says: "It is the biggest takeover deal in Asia ever. HKT is unbelievably important to the Hong Kong market. A change in control of this size is significant for Asia. It is also very significant that the bidder is an internet company. It shows a lot about the credibility of this new market."
Evans says that the deal was pushed through so quickly because Singapore Telecom was finalising its rival bid, believed to be of a similar value.
Teams in London and Hong Kong worked on the deal 24-hours-a-day by exploiting the 11 hour time difference between the two cities.
Corporate partner Don McGown was a member of A&O's London team. Hong Kong corporate partner Nick Gibbon also advised.
Simmons' London team included corporate finance partner Damon Le Maitre-George and banking partner Nick Fisher. Its Hong Kong team was led by corporate partner Nick Norris, telecoms partner Daniel Leiu, and banking partner Jeremy Hoyland.