The Abbott government wants the royal commission into child sexual abuse to be given another two years and an extra $126 million to complete its historic inquiry.

Attorney-General George Brandis on Tuesday announced the government has asked the governor-general to extend the commission’s reporting deadline to December 15, 2017.

The extension would give the commission the capacity to hear more stories from victims, conduct more public hearings and issue extra interim reports.

It’s anticipated an additional 30 public hearings, 3000 private sessions and dozens of research projects will be possible with the extra time and funding.

“All of this will build a much fuller and more complete picture of the scourge of institutional child abuse,” Senator Brandis told the chamber.

“Most importantly, it will give those who need to tell their stories the opportunity to do so.”

Senator Brandis said the additional funds brought the total government outlay to $500 million, a “significant amount” but entirely justified.

He’d been assured by the commission’s chair Justice Peter McClellan AM that the extra time would be sufficient to complete its vital work.