Queensland Police said they were still receiving emergency calls, but the New South Wales force people should contact authorities on 131 444 as triple-0 calls were still interrupted.
A spokesman for Victoria's emergency call answering service ESTA said it was aware of the problem, but urged people to keep trying triple zero if they can not get through on the first go.
According to Telstra, the cut cable caused "intermittent mobile voice connection interruptions" across the four states, including to 000.
A fibre fix crew are on site at a cable pit east of Orange, the telco said.
"We're working closely with emergency services in those States".
Vodafone also said Ambulance Victoria had advised people in Victoria who did not get through to triple zero ths first time to keep trying.
Brokerages Set G4S (GFS) Price Target at $312.78
Numis Securities upgraded shares of Ocado Group (LON:OCDO) to a buy rating in a report published on Wednesday morning. The Asset Advisors Corp holds 42,140 shares with $6.57 million value, up from 39,940 last quarter.
Telstra is assuring residents in New South Wales, Western Australia, Queensland and South Australia that an issue affecting calls to Triple-Zero has been resolved.
UPDATE 9.20AM: TELSTRA has revealed a lightning strike is the cause of a major service outage across the country today.
"We're making every attempt to call them back", he said. "Current impact mostly in NSW & some interruptions in VIC, SA & WA", the telco tweeted at around 8.30am AEST on Friday.
Queensland Police said there had been some issues on the Sunshine Coast but the problem did not appear to be widespread.
The issue on Tuesday was caused by technical changes made ahead of upgrades to mobile traffic control equipment in Telstra's Exhibition Street exchange in Melbourne, the Telstra spokesman said.
It is not believed the latest outage has anything to do with the issues experienced by Telstra customers earlier in the week.