The merged firm has 2800 lawyers, including 450 partners, in its 20 offices across Asia, UK, US, EMEA and Australia.

The full equity merger, agreed by the partnerships of Freehills and Herbert Smith in June this year, has created a firm that will operate under a single profit pool from Monday 1 October.

The firm said today that comprehensive integration plans have been put in place and are not being rolled out.

David Willis and Gavin Bell will be the joint CEOs of Herbert Smith Freehills.

Willis said a priority of the merged firm will be further international expansion.

Since the merger was agreed in June, Herbert Smith has opened a new office in New York and has confirmed plans for Herbert Smith Freehills to establish a presence in Germany, South Korea and Francophone sub-Saharan Africa in 2013.

“We recognise that the firm's global reach, when combined with our industry sector strengths and balance of disputes and transactional expertise, will be the foundation on which we can build strong and deep client relationships,” Willis said.

Former Freehills CEO Gavin Bell said client response to the merger has been positive, and recognise  the benefits a global perspective will bring to their matters.

"This merger reflects the changing global landscape and the rebalancing of world economies.  Over the next decade Asia Pacific will increasingly become the engine room of the world economy, and as the leading integrated firm in the region we will be ideally placed to help our clients take advantage of that."