King & Wood Mallesons (KWM) has appointed a new Australia managing partner just days after the announcement that its former country head, Tony O'Malley, is to step down.

Landing the top job is Sydney-based partner Sue Kench, who is also head of the firm's construction and property practice and who has been employed with Mallesons Stephen Jaques for 20 years.

In a statement, the firm said Kench's appointment was effective immediately and that she will be the first female in the role.

"I am delighted with the board's decision," commented KWM's global managing partner Stuart Fuller.

"Sue possesses the stewardship and energetic drive for excellence that is critical to executing the firm's domestic strategy and broader integration into the region and internationally."

Last week, KWM announced that Tony O'Malley was to quit as Australia managing partner after just 14 months in the job.

O'Malley, who was appointed country head in January 2012 after 13 years at Mallesons, will retire as a partner of the firm on 31 December this year.

The firm has so far declined to comment on the reason behind his sudden departure, but sources in the market suspect there may have been differences within the board regarding management styles.

Currently the board is looking to grow KWM's international presence through partnerships with other firms.

Earlier this year it was in talks with Singapore's Wong Partnership about the possibility of tie-up, but discussions came to a halt when Wong Partnership made the decision to stay independent.

The firm is also considering a merger with UK firm SJ Berwin. 

Kench, who made partner at Mallesons in 1996, was on the board of the legacy firm when it decided to join with China's King & Wood in March last year through a Swiss verein.

In her first comments since being promoted, she admitted that times were tough for law firms in Australia.

"Competition for clients and deals in the Australian market remains fierce and, if anything has intensified this year, as commercial activity and confidence in the broader economy remains challenged.

"Our historic combination with King & Wood last year has given the firm a unique point of difference in the market and I look forward to working with the board, all the partners throughout the KWM network and the rest of the leadership team to continue our bold strategy to become the leading global law firm based in Asia."