The plan, which was approved by votes at both firms Friday, will see Blake Dawson adopt the Ashurst brand in Australia as well as in the combined Asia offices. The integration of the Asian offices and the re-branding of Blake Dawson are due to take effect March 2012, with a vote on a full merger envisioned about two years after that.

The news comes just after Blake Dawson announced it would launch a new practice in South East Asia, headed up by former Freehills practice head, senior associate George Cooper. See the full story here.

Just last month Blake Dawson refused to confirm reports it was considering a merger with the UK firm. See full story.

The deal between Ashurst and Blake Dawson is the latest in a string of deal between British and Australian law firms. 

Norton Rose started the trend in 2009 with the announcement of a combination with Deacons. Earlier this year, Clifford Chance acquired two small firms in Sydney and Perth, and DLA Piper fully merged with DLA Phillips Fox, which became DLA Piper under the deal. 

But Blake Dawson is the largest and most prominent Australian firm to date to engage in an international tie-up. 

If the merger took place today, it would give the merged firm more than 1,700 lawyers and revenue of around $850 million, the firms calculate. 

Ashurst Asia head Geoffrey Green, a former senior partner, will head the merged Asia practice, which will have about 150 lawyers in the beginning. The 900-lawyer British firm now has about 75 lawyers in Asia, with about 30 lawyers in each of Hong Kong and Singapore, as well as a smaller office in Tokyo.

Blake Dawson will contribute about 75 lawyers to the combined practice, and will draw from offices in Shanghai, Singapore, Tokyo, New Guinea, and Indonesia. Australia-based Blake Dawson partners whose practices are predominantly focused on Asia will also be part of the Ashurst Asia group.

Leaders at both firms say they saw the deal as a way to quickly ramp up their presence in Asia.

Blake Dawson managing partner John Carrington said the tie-up provides the with a level of critical mass in the region that would have been hard to achieve without the merger.

"Our firms have worked together successfully in Asia for nearly 10 years. This combination is a natural development of our relationship, giving Ashurst scale and depth of resource in Asia and providing our Blake Dawson colleagues with greater international reach for their important client base. We both look forward to full integration."

Green said Ashurst sees the deal as a chance to make up ground with Magic Circle firms that have many more lawyers on the ground in Asia. "They have a significant resource base that we don't," he said. 

"It would be difficult for us to build that organically. We needed to do something that increased the pace of our growth."

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