A defiant Kim Williams said he was under no illusions and expected a funding review and potential cuts to the ABC under a Coalition government, saying he was ready to defend the broadcaster’s efficiency, declaring it was “game on”.

The ABC chair responded to Peter Dutton’s comments on Wednesday about potential cuts, saying it is “important to indicate that this is not a fresh observation” from the Liberal Party leader.

“I don’t think there’s any doubt that in the event of Mr Dutton acceding to office, that there will be a very early call for an efficiency and apparently an excellence review on what the ABC does. Game on,” Williams said at an address at a Melbourne Press Club event on Thursday.

“The ABC is an accountable institution, and I have no doubt it will perform well.”

There have been numerous inquiries on the efficiency and quality of the ABC going back to the John Howard government, Williams said, many of which have recommended an increase to its funding.

In total, there have been 15 reviews of the ABC’s efficiency since 2001.

Williams’ keynote speech was wide-ranging, emphasising the need to “flood the zone with truth”, while pushing back on threats to media freedom, such as billionaire Jeff Bezos’ “appalling behaviour” as owner of The Washington Post.

Reflecting on his first year as ABC chair, he said there are some areas where the broadcaster had significantly “lost the plot” and drifted.

“I think it’s underperforming in documentaries is deeply alarming, and it needs to be corrected and redirected as a matter of urgency,” Williams said.

Williams also broke down in tears twice, while reflecting on the positive messages he has received from its audience on the impact of its work, in particular the service it provided during Cyclone Alfred in Queensland last month.

Dutton foreshadowed cuts to the public broadcaster on Wednesday while speaking to ABC Radio Melbourne, saying the Coalition would “reward excellence” when asked by host Raf Epstein if the broadcaster would be part of his wider plans for cuts.

“I think there’s very good work that the ABC does, and if it’s being run efficiently then [we’ll] ... keep funding in place,” he said. “If it’s not being run efficiently ... taxpayers pay for it, who work harder than ever just to get ahead, [they] would expect us to not ... support the waste.”

Labor quickly pounced on Dutton’s comments, to which he added during several media appearances that day, with the party warning voters that Dutton had shown his hand, and asking for donations to help “fight for” a properly funded ABC.

More to come.

Cut through the noise of federal politics with news, views and expert analysis. Subscribers can sign up to our weekly Inside Politics newsletter.