Telstra is not saying how many jobs may be lost as part of a major restructure of its internal operations.

Australia’s largest telco is expected to outline how many of the company’s 30,000 Australian staff will be affected by the changes in the coming weeks.

A number of new jobs are set to be created by the changes, but that is unlikely to offset the number of positions to be cut.

Telstra chief operations officer Brendon Riley told staff on Wednesday the company’s operations unit had to evolve in order to support future needs.

“Our traditional businesses are coming under increasing margin pressure and the largest portion of our budget is spent supporting them,” Mr Riley said in a memo.

“This is not a sustainable business model and we have an obligation to redefine our contributions to Telstra.”

The restructure of Telstra’s operations unit, which Mr Riley described as the most substantive in 10 years, will start on July 1.

Telstra has shed about 2,000 jobs since the beginning of 2012, with staff either made redundant or their jobs sent offshore from a range of different businesses.