Optus bought exclusive Australian broadcast rights to the majority of World Cup games from SBS, a deal Fairfax Media estimated to be worth $8 million.

Customers encountered problems with Optus Sport's streaming service during the early stages of the event.

The issues prompted a series of crisis talks this week and Wednesday's unprecedented action.

Optus chief executive Allen Lew has revealed his organisation will continue to stream matches, but all pool clashes will also be telecast on free-to-air TV.

Customers who have paid $15 to access Optus Sport during the World Cup will receive refunds.

Optus is also providing all Australians with free access to its streaming service until August 31, a date that includes the start of the English Premier League season.

"We're not perfect. We've made a mistake," Lew told reporters.

"I don't have any regrets about spending (millions to acquire World Cup rights) ... business is all about taking risks, in our industry you have to be bold.

"We stumbled on Sunday.

"But we learned some very important lessons. We will be better for it and Australian consumers will benefit, because it will have a positive flow-on effect with EPL and the next big event we take on to stream."

A decision on round-of-16 clashes and quarter-finals, some of which were intended to be exclusive to Optus, is yet to be made.

"If we take it exclusively, we will make sure we'll be able to deliver a good experience to all Australians," Lew told reporters.

"We've made sure our network is a lot more resilient."

It isn't just viewers that Optus must now work hard to appease. Broadcast partners are also understandably furious.

"Live sport streaming on mobile internet is an emerging technology. We are all learning as we go along. I think our partners fully understand the risks involved," Lew said.

"We will work with them ... now that we are making it free, we expect a lot more people on the app."

Frustrated football fans flooded social media with complaints last weekend. A phone call from Prime Minister Malcolm Turnbull to Lew followed on Monday.

Lew insisted Wednesday's decision was a matter of giving Australians "choice", rather than a reflection of the telco's capabilities.

"Since Monday, we have continued to improve our product and Optus has delivered the last six matches of the World Cup without issue," Lew said.

"This has provided confidence.

"However confident we are in our capabilities, we have listened to the feedback from Australian soccer fans."

Australian Associated Press