Telstra pushed to increase its wholesale prices by 7.2 per cent this month in a move that would affect millions of customers at rival telcos. It said the move of customers onto the NBN meant those remaining on its copper network would need to pay more to help the company recover its costs.

Competitors including SingTel-Optus chairman Paul O'Sullivan have been calling on the Australian Competition and Consumer Commission to reject the move and include payments from Telstra's deal to help build the national broadband network when considering any price adjustments.

But in a statement on Wednesday morning, ACCC chairman Rod Simsrejected these calls and said the payments would not be included in any calculations as the NBN took over as Australia's core telco network.

"The ACCC will use the regulatory value of Telstra's assets, not the higher payments agreed between Telstra and NBN Co in their Definitive Agreements, to adjust the cost base for NBN effects when determining regulated charges," he said. "This is a straightforward matter and our approach accords with common regulatory practice."

He said complaints on the issue from Telstra's rivals were little more than an attempt to claw back money from the telco giant.

Mr Sims told Fairfax Media: "The more we thought about this, the more it became extremely clear what the right answer is. It was a bad look a debate to be going on for nine months.

"I've been through all their arguments on the issue... they're just saying Telstra's got a lot of money and we'd like a way to claw that back, [but] we as a regulator cannot do that."

He also said including the value of Telstra's NBN deal would in fact increase the chances of prices going up, because the entire network would have to be revalued according to the $11.2 billion deal.

Telstra chief executive David Thodey said he was pleased to get clarity on the issue.

"It's a good step along the way," he said. "We are in agreement.

"[The ACCC] should look at all the utilities such as power and water ... it's just purely [that] the cost base of running big networks goes up and yet the demand as the NBN rolls out declines."

However, Mr Sims added that the value of Telstra's network would decline over time as it handed over the copper network to NBN Co as part of the deal.

Telstra's rivals said this was a key point that worked in their favour and vindicated some of their arguments because it would lower the amount the telco could charge for access to the network.

"Optus welcomes confirmation that NBN Co's payments to Telstra will be taken into consideration in setting access prices," a spokeswoman said. "This is a position Optus championed to ensure that Telstra doesn't double dip and get two payments for the same asset".

The Competitive Carriers Coalition, which represents rivals such as Vodafone Hutchison Australia and Macquarie Telecom, said the ACCC's decision was a mixed result.

"On one hand, Telstra will enjoy windfall gains worth billions of dollars from the payments without having that considered as revenue," it said. "On the other hand, Telstra will not be able to completely "imagine away" the NBN and force consumers stuck on its old network to compensate it completely for those consumers lucky enough to be moving onto the new network."

The ACCC's decision came after Communications Minister Malcolm Turnbulland Finance Minister Mathias Cormannmade the rare move of sending the regulator a letter asking them not to include the NBN deal and warning that to do so risked making it collapse.

Mr Sims said: "I accept it's prompted by the Minister's letter, but it didn't affect any adjustments.