Allen & Overy (A&O) has asked a number of Hong Kong partners to leave as the firm cuts back its local partnership by around 20%.

The magic circle firm confirmed that it has asked four partners to leave, with the group understood to include partners from both transactional and disputes teams, while one further real estate partner has left the firm to set up his own practice.

The departures represent almost one-fifth of the firm's partner headcount in Hong Kong, which currently stands at around 25. However, the firm said that none of its 80 Hong Kong associates will be affected by the partner exits.

Other recent changes in A&O's Hong Kong office have included one partner retirement at the end of April, while corporate partner Vivian Yiu was made up in the firm's promotions round earlier this year.

An A&O spokesperson said the role of Hong Kong as a regional hub has changed for the firm, which has grown its Asia headcount by 60% in the last four years. The magic circle firm announced last month that it is set to launch in Vietnam later this year, while it also last year entered the Indonesia market via an exclusive association agreement with Jakarta's Ginting & Reksodiputro.

A&O, which has also recently grown its Beijing and Shanghai offices, was one of the earliest firms to gain a local law licence in Singapore when the first round were handed out in 2008, although talks over a tie-up with local leader Allen & Gledhill were called off in March this year.

News of the Hong Kong cutbacks comes amid a recent slowdown in work in the region, including a drop-off in activity in the much-touted initial public offering market which has seen the cancellation of a number of high-profile Hong Kong listings.

Top US firms including Kirkland & Ellis and Davis Polk & Wardwell have also aggressively moved into the market of late, putting pressure on partner and associate pay rates and increasing the competition for work.

A&O last year saw the departure of two banking lawyers to Kirkland, with partner Ashley Young and senior associate Douglas Murning both joining the US firm as partners alongside hires from Latham & Watkins and Skadden Arps Slate Meagher & Flom.

A&O's Hong Kong office also lost a seven-partner team – including former Asia corporate chief Michael Liu – to elite US firm Latham & Watkins in 2008.