Bird & Bird has sealed a merger with its Australian ally Truman Hoyle, some 18 months after the two firms announced an association.

Partners at the UK firm approved the deal last Tuesday, Legal Week understands, having voted on the tie-up over the last two weeks.

The merger will go live on 3 November, with Truman Hoyle to be rebranded as Bird & Bird Australia and the total number of Bird & Bird offices globally to reach 27.

Some 25 fee earners and eight partners from Truman Hoyle – a Sydney-based technology boutique with a turnover of around £4.4m in 2013-14 – are to move onto Bird & Bird's remuneration structure and IT systems, with the office to be run by the current Truman Hoyle managing partner Shane Barber.

Head of Asia for Bird & Bird Justin Walkey told Legal Week that financial integration would help create a more joined up Asia Pacific offering and give the firm a clear advantage when pitching for regional work.

It would also increase the firm's access to talent in areas such as competition law, said Walkey, with Australian lawyers able to play a key role in developing the practice in South East Asia.

Walkey added that he would ideally like to double the size of the Australian partnership in the next three to five years and hoped it would account for around a fifth of regional revenue within the same timeframe.

An office in Melbourne could also be on the cards subject to economic factors and the pace of business growth.

"The ambition is to build a leading technology and IP practice in Australia," he said.

"[The office] will definitely be bigger; an obvious gap is IP litigation – Bird & Bird will be wanting to fix that quickly.

"We have no reason to be in every single state in Australia, but if there was to be an expansion it would be into Melbourne – I could envisage a Melbourne operation in time.

"[In three to five years] it could be contributing around 15-20% of Asia Pacific revenues."

Bird & Bird first entered Australia in March 2013, following in the footsteps of UK rivals Norton Rose, Allen & Overy, Herbert Smith and Ashurst.

The firm's approach was considered to be among the more cautious models – an initial alliance allowing it to 'test the waters' before entering into a long term commitment.

Outside of Australia it has signed similar strategic cooperation agreements in South Korea and Indonesia in the last 18 months. The Indonesian deal may also lead to financial integration, according to firm CEO David Kerr.

The firm's local partners in the two countries are corporate outfit Hwang Mok Park in Seoul, following a tie up in March, and K&K Advocates and Nurjadin Sumono Mulyadi & Partners in Jakarta, following a combination announced in June.