NBN Co is expecting to hit “new problems” in its rollout as the company’s contractors begin connecting more of Australia’s high-density city areas to the network this year.

CEO Bill Morrow warned city residents to prepare for “disruption” from civil works as more of NBN Co’s 14,000-strong contract workforce become visible on city streets.

“As the NBN network rolls out into cities we will be met with new problems to solve,” Morrow said in a statement.

“We understand there will be some disruption for residents and business owners,” he said, though he added that “the payoff will be worth it”.

Morrow also attempted to counter recent criticism that the network rollout is proceeding too slowly to hit the 2020 deadline for network completion.

News Limited papers reported earlier this month that NBN Co would need to quadruple the rate of network connections it made in 2016 in order to reach its targets.

Morrow said he was aware of the challenges to complete the project by 2020, but said he was confident that the company’s “strong foundations, processes and systems” would enable the rollout to scale as needed.

“The intensified deployment will present challenges but the NBN team, along with our partners and retailers, is focused on a positive experience for customers and end users as we accelerate the build and connection rates to new records,” he said.

Morrow said NBN Co was aiming to have “almost” half of the network rollout completed by the end of June this year.

That would mean a total network footprint of 5.4 million homes and businesses. As at the time of writing, NBN Co had passed 3.82 million premises.

“To date more than 70 percent of NBN’s rollout has happened in regional and rural areas,” he said.

“This year will see more construction commence in metropolitan areas along with our continued work right across the country.”

Some city users are likely to be beneficiaries of NBN Co's recent addition of fibre-to-the-distribution point (FTTdp) to its multi-technology mix. It is being flagged for use in Sydney and Melbourne to begin.

NBN Co has some experience in deploying the network in high-density areas due to its competition with TPG to bring fibre-to-the-basement (FTTB) to lucrative high-rise complexes.