DLA remains top of global rankings as Australia and Canada tie-ups transform UK firms' footprint abroad

Norton Rose and Ashurst have emerged as the fastest-growing firms over 2011-12 in Legal Week's global rankings, which take into account revenues generated across both UK and international profit centres tied with the firms.

Norton Rose's global revenues – which this year include its Swiss verein mergers in Canada with Ogilvy Renault and Macleod Dixon and South Africa's Deneys Reitz – have risen by 68.5% to reach £822.3m, placing it seventh in the ranking, which includes full global revenues of UK law firms operating through Swiss verein-style structures, as well as formal alliances.

The revenue total also includes the firm's Swiss verein merger with Australia's Deacons, which went live during the previous financial year.

Ashurst has also seen a year of significant expansion, with the firm's tie-up with Australia's Blake Dawson going live in March. The pair, which plan to complete a full financial merger in 2014, have already combined their businesses in Asia, with Blakes rebranding as Ashurst across Australia.

The Australian firm took in revenues of A$398m (£264m) for the financial year to 30 June, with the combined revenue total standing at about £586m.

Ashurst managing partner James Collis commented: "The opportunities provided by Ashurst in Australia make us optimistic about the coming financial year. The combination increases our geographical hedge, as well as our practice hedge, which is important in such a turbulent market."

DLA Piper has remained at the top of the ranking, which Legal Week introduced last year to reflect UK law firms' increasingly international presence.

The firm has continued to grow this year, reporting global fee income of £1.4bn – a 10.4% increase on 2010-11, due to expansion, including its full financial integration with Australian best friend firm DLA Phillips Fox.

The global ranking also takes into account formal international alliances such as Eversheds International and the CMS network, both of which are pushing forward with plans for closer integration.