Optus network interference not delaying NBN wireless rollout

NBN Co has denied a claim by Shadow Communications Minister Malcolm Turnbull that interference between Optus' mobile network and NBN Co's fixed-wireless network is delaying the rollout of the network.

NBN Co and Communications Minister Stephen Conroy have denied a claim by Shadow Communications Minister Malcolm Turnbull that the wireless rollout of the National Broadband Network (NBN) has stalled because the network interferes with Optus' existing network.

The fixed-wireless long-term evolution (LTE) component of the NBN rollout was due to reach 70,000 premises by the end of this month, but recent reports have suggested that NBN Co will struggle to meet even 45 percent of this goal due to difficulty with poor premises location information and problems with getting the signal to reach premises through tall trees.

But Turnbull has today claimed that another issue may now be impacting the fixed wireless rollout, suggesting in parliament and again on Sky News that the NBN network may interfere with Optus' existing mobile network.

"If the NBN Co has acquired spectrum which in the areas where it overlaps with Optus creates interference issues, now that's going to require some delicate sorting out. They may have to exchange some frequencies," Turnbull said.

An NBN Co spokesperson said that the spectrum issue is not delaying the wireless rollout. Additionally, Conroy told the parliament today that there is always coordination between telcos on spectrum in the same band.

"There are always issues between different networks," Conroy said.

"It may come as a surprise to the opposition that the laws of physics apply in this instance. But it's not a surprise for those at NBN Co."

Optus said the discussion between NBN Co and Optus is normal practice.

"Spectrum coordination to avoid interference within geographic areas is a normal part of building telecommunications networks," an Optus spokesperson told ZDNet in a statement.

"As per global industry practice, Optus has been in constructive dialogue with NBN Co to put in place a series of practical network guidelines to prevent interference where NBN Co base stations are located close to Optus base stations."

NBN Co paid Austar AU$120 million for its spectrum in the 2.3GHz and 3.4GHz bands back in 2011 .

AAP contributed to this story.