Allen & Overy (A&O) has secured the eye-catching hire of two New York energy and infrastructure partners from magic circle rival Freshfields Bruckhaus Deringer, in a rare move between top-tier UK firms in the US.

US energy and infrastructure head Kent Rowey and fellow partner Dolly Mirchandani are both leaving Freshfields to join A&O's base in New York. Mirchandani is also Freshfields' global co-head of pro bono.

The hires for A&O mark an unusual move for a magic circle firm in the US, where the UK's leading firms have to date generally built up their practices with hires from domestic outfits.

Rowey has been a partner at Freshfields since joining the firm in 1996 from US firm Perkins Coie, while Mirchandani joined the firm in 2000 and made partner in 2005. Both partners focus on the finance side of the energy and infrastructure sector, advising lenders, public authorities, developers and investors on projects and transactions.

The hires will grow A&O's US energy and infrastructure practice to around 30 lawyers, including nine partners. The firm is expecting to grow the team by a further 30%-40% by the end of the year.

A&O US managing partner Kevin O'Shea said: "Opportunities like this don't come around very often. The combination of our strategic focus on domestic energy & infrastructure and Kent & Dolly's reputation in this area makes for a very compelling proposition. The prospects for our energy and infrastructure practice are incredibly exciting."

Freshfields has around 30 partners across its two US offices in New York and Washington DC.

In a statement, Freshfields said: "We thank Kent and Dolly for their efforts and contribution to the firm's success and we wish them all the best for the future."

The news comes on the back of another high-profile hire for A&O's US practice, with senior US Department of Justice DoJ antitrust lawyer John Terzaken joining the firm's Washington DC office earlier this summer.

Terzaken, the DoJ's former director of criminal enforcement in its antitrust division, joined A&O's nine-partner Washington practice in August as a partner and head of its US cartel defence practice.