(Reuters) - Singapore Telecommunications' Australian unit Optus said on Monday it had appointed Stephen Rue as its new CEO, nearly half a year after former boss Kelly Bayer Rosmarin resigned following a massive network outage.

Optus' finance chief Michael Venter will continue as the interim CEO until Rue, currently the head at Australia's national broadband network, takes over later in November, the telecom firm said.

The announcement comes at a time when market speculation is rife that Singapore Telecommunication (SingTel) is looking to sell part of entire stake in Optus. The Singapore firm has denied the speculation multiple times.

In early November last year, Optus, Australia's second-largest telecom operator, suffered a 12-hour network blackout which impacted more than 10 million Australians and left them without internet or phone access.

Rosmarin resigned just weeks after, cutting short a more than three-year tenure that was also marred by one of Australia's largest data breaches.

Separately, SingTel last week flagged it would report a net loss for the second-half of fiscal 2024, citing non-cash impairment provisions of S$3.1 billion ($2.30 billion), of which about S$2 billion was for Optus' goodwill.

($1 = 1.3496 Singapore dollars)

(Reporting by Rajasik Mukherjee; Editing by Lisa Shumaker; Editing by Shri Navaratnam)