"Even under a de-merger, the two companies would be owned by the same set of shareholders, so we need other reforms," said Mr Sheridan.
"Otherwise the new network entity could say, 'My biggest customer is Telstra Retail so I am going to start cutting it some special deals.' "
Optus also wants new pricing rules to ensure that a demerged network company would not abuse its dominant market power.
"We welcome the NBN and fact the government has recognised we have a dysfunctional market structure that is not benefiting consumers," Mr Sheridan said. "The current system can't control Telstra.
"Our key theme is that model the government thinks best serves customers of the NBN is a structurally separated model and we are saying that should be implemented today."
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