Standard & Poor's is keeping Chorus' credit rating on negative watch until it sees how the telephone lines company is going to mitigate last year's adverse pricing ruling.
In November, the Commerce Commission ruled Chorus must halve the wholesale price of broadband access to its copper wires to $10.92 per customer from December next year.
S&P credit analyst Paul Draffin says the agency believes Chorus is committed to maintaining a BBB credit rating and that it has a number of operational and capital management options.
Chorus has estimated the ruling will cost it about $142 million a year in operating earnings and about $1 billion by 2020.
Mr Draffin says a number of the measures Chorus could take could be risky to put in place and complicated by the company rolling out the ultra-fast broadband network.
He says the objective is to resolve a watch within three months, but it can only do that where it has the necessary information.
Mr Draffin says the strategies that the company may need to employ to maintain its BBB rating would have significant consequences for its stakeholders.
"To bridge the funding gap and maintain the triple B rating will require some quite significant operational and capital management strategies by the company, it is unclear at this point exactly which of those strategies the company will employ - so we will leave it on credit watch until we fully understand those strategies."
Mr Draffin says it's unclear at this point whether any strategies Chorus undertakes will be significant enough to maintain the BBB rating, which is why S&P has left the company on credit watch.