PwC has a substantial presence in Papua New Guinea.
The move will involve partner retirements and staff redundancies but the firm did not specify the breakdown between the groups.
The move to cut staff comes two weeks ahead of the end of PwC's "reduced working week program" under which the pay and hours of underused staff was cut by at least 20% since mid-April - a 4% annualised reduction.
At the time, staff were told the move was designed to "protect jobs and not make people redundant".
Staff on the reduced working week will receive redundancy entitlements based on their regular, full-time pay.