In an e-mail titled "Staying competitive", a copy of which was obtained by Computerworld, O'Sullivan said a "combination of permanent and contract positions as well as vacancies that won't be replaced" will be cropped across the entire business.

"We are finalizing the actual number of jobs that are likely to be directly impacted and expect this to be around 200," O'Sullivan wrote. "We will be striving to keep this number to the absolute minimum."

Optus' total headcount is about 10,000 and the company will speak with each of the individuals affected to discuss their situations and any alternative employment opportunities, according to O'Sullivan; however redundancies "will not be voluntary".

"They will result from areas where we have decided to streamline management or alter our operational costs," he wrote. "We will engage an external provider for counselling and career services to support the best personal outcome for those people impacted."

While "the size of these changes can't be summed up in one e-mail" O'Sullivan will explain over the next three months how management plans to restructure the business.