NBN Co has secured $6.1 billion from banks to bolster its working capital.

Finance Minister Mathias Cormann says the local and international banks have “demonstrated … strong support in the market for the NBN business plan and outlook”.

NBN Co has sourced an additional $4.1 billion - on top of an initial $2 billion it borrowed in mid-2018 - “at very competitive prices” via “arrangements with a number of Australian and international banks”, Senator Cormann said.

“There is no requirement for NBN Co to draw down on these additional facilities immediately, but the Government agrees with the company that it makes sense to have these facilities in place, to give it flexibility and given current economic conditions,” he said in a statement.

“The additional funding will provide the company opportunities to invest and create even more value for Australians guided by future corporate plans,” Communications Minister Paul Fletcher said.

NBN Co “is expected to draw down $2 billion” of the $6.1 billion total to cover increased build costs caused by delays to its HFC rollout and fixed wireless congestion remediation.

Of the new $4.1 billion, $1.5 billion “will be reserved for working capital to provide the company with added flexibility and to support NBN Co’s long term capital management strategy,” the Government said.

Some of that money could “pay down” NBN Co’s existing $19.5 billion loan from the Government “without jeopardising [NBN Co's] performance”.

“The balance of funds is available for strategic investments with a positive return beyond the initial rollout phase and repayment of the Commonwealth loan, subject to shareholder approval.”

NBN Co's CFO Philip Knox says the new money represents “an important next step for us as we approach the completion of the rollout”.

But, he said, “the pricing of the new facilities is in line with debt pricing for high investment grade Australian corporate borrowers”.

“The financing ensures NBN Co has adequate liquidity and supports our long-term financing strategy of diversifying our funding sources,” Mr Knox said.