ABC managing director Mark Scott has launched a spirited defence of the network after Prime Minister Tony Abbott questioned its loyalties and announced a snap inquiry into Monday night’s Q&A program which featured a former terror suspect.

While Mr Scott said the ABC would cooperate with the inquiry – and had already launched one of its own into Q&A – he rejected any suggestion the network might be aiding terrorists through some of its editorial decisions.

“The ABC is clearly Australian, it’s on the side of Australia,” Mr Scott told an audience of public affairs specialists in Melbourne on Thursday night. “The A in ABC is for Australian.”

Read an edited extract of Mark Scott’s speech here

Mr Scott said the ABC’s role of being an independent public broadcaster was “a vital one, central to our culture and our democracy”, but it should never become a “state” broadcaster.

“A state broadcaster is the communications arm of the Government,” Mr Scott told the Centre for Corporate Public Affairs.

“Its role is to communicate the messages of the Government – and certainly not to do anything that undermines the Government.

“I hope no one seriously wants the ABC to be a state broadcaster.

“We know the examples. North Korea and Russia. China and Vietnam. There are many others.”

This was seen as a thinly-veiled slap down of Mr Abbott, who on Tuesday launched an attack on the ABC after the national broadcaster allowed terror suspect Zaky Mallah into the audience of Q&A.

Tony Abbott (L) and Communications Minister Malcolm Turnbull in question time. Photo: AAP

The 30-year-old was acquitted in 2005 on terror charges after he made a video which allegedly contained a threat to carry out a suicide attack on federal government offices in Sydney.

Mr Abbott said the ABC had betrayed Australians by giving Mallah, who had been vetted by program producers, a platform.

“The ABC needs to have a long hard look at itself. And I pose the question again: whose side are you on here?” he asked, after telling the party room the program was a “lefty lynch mob”.

The strong criticism continued on Thursday when Mr Abbott said the ABC should sack the people responsible for the appearance.

“They compounded the mistake by re-broadcasting the program,” he said. “Now, frankly, heads should roll over this.”

Mr Abbott announced that he had ordered an “urgent government inquiry” into the live appearance, unsatisfied that the ABC’s internal inquiry into the show would be sufficient.

“So often we’ve seen virtual whitewashes when that sort of thing happens,” he said.

Mr Scott conceded the public broadcaster did not adequately consider the risks of having Mallah in the Q&A audience.

“The risks and uncertainties of having him in a live programming environment weren’t adequately considered before the decision was made to accept his application to be in the studio audience,” he said.

But the ABC boss strongly rejected the Prime Minister’s claims, saying that independence was the cornerstone of the broadcaster’s credibility.

“The ABC Act does not envisage the ABC as another branch of Government public relations. Instead, it asks the ABC to provide an independent national broadcasting service. And the Board is asked to maintain that independence,” he said.

“There are good reasons for independence from Government, just as there are good reasons for an independent judiciary.”

Mr Scott said Australians cherished freedom of expression, cherish debate and “cherish the role of the ABC in facilitating both”.

“Instead, Australia has an independent ABC and that independence is key to its credibility. It’s why trust in the ABC is streets ahead of commercial media.”