Gibson Dunn & Crutcher has further strengthened its London corporate offering by hiring another Ashurst partner.

Financial regulatory partner James Perry is the latest in a string of Ashurst partners to leave the firm for Gibson Dunn in the City, including former senior partner Charlie Geffen.

Perry's regulatory and transactional practice has a focus on the financial services and insurance industries.

He has advised clients including Credit Agricole, Societe Generale and Royal & Sun Alliance. He made partner at Ashurst in 1998.

Geffen said: "As we grow our transactional practice in London, we will increasingly require regulatory expertise from a known market practitioner.

"Jim is a leading lawyer in the sector, and with his arrival, the firm will be able to offer high-quality financial regulatory advice on both sides of the Atlantic."

Geffen joined Gibson Dunn in 2014 taking with him corporate partner Mark Sperotto. Geffen left for Gibson Dunn a year after losing out to Ben Tidswell in the partner vote for Ashurst's chairman position.

The moves followed those of former Ashurst partners Jonathan Earle and Nigel Stacey who jumped to Gibson Dunn in the summer of 2014.

The firm has also brought on board a number of other high profile hires including senior finance partner Stephen Gillespie from Kirkland & Ellis in December 2014 and most recently Herbert Smith Freehills' capital markets head Steve Thierbach and fellow partner Chris Haynes.

Gibson Dunn has made no secret of its ambition in London. Last year global managing partner Ken Doran told Legal Week: "We do not seek to be the largest firm, but we do aim to be included in any discussion of the very best firms."

Geffen and Doran agreed they see an opportunity in London as the top UK firms gear themselves towards operational efficiency, increasing partner-to-lawyer leverage. In contrast, Gibson Dunn is aiming to work on a low-leverage ratio, approaching clients with the promise of partner attention.