ABC boss confirms ex-news director in the dark about replacement hunt

Hugh Marks has faced questions over Justin Stevens's resignation. (ABC News: John Gunn)

ABC managing director Hugh Marks has faced questions from Radio National Breakfast show host Sally Sara over the resignation of former news director Justin Stevens.

Mr Marks said he and Stevens had a fundamental disagreement over the future of ABC News, and confirmed reports the process to replace Stevens was underway well before he tendered his resignation.

Stevens's replacement, Reuters deputy editor-in-chief Simon Robinson, will begin as news director in September.

ABC managing director Hugh Marks has confirmed former news director Justin Stevens was not aware a selection process for his replacement was already underway before he resigned from the ABC late last month.

Mr Marks revealed more details about the sudden departure during an interview with Radio National Breakfast host Sally Sara this morning, in which he also addressed the controversy surrounding the hiring of former Australian of the Year Grace Tame to host an ABC podcast series.

Asked why the ABC had thought it necessary to seek a new director of news, Mr Marks insisted Stevens's exit was a resignation, but said it had occurred in the context of a fundamental disagreement between the pair over the future of ABC News.

The national broadcaster is facing a number of challenges around resourcing live news and exploring different formats, he said, and "maybe we felt there were different directions to pursue".

Stevens announced his resignation on May 27. His replacement, Reuters deputy editor-in-chief Simon Robinson, was announced the following day.

Mr Marks also confirmed media reports that a formal process to find a replacement for Stevens was underway well before the news director tendered his resignation, saying he had engaged a recruitment firm as part of "general sort of succession planning" once he came to believe Stevens's resignation was likely "inevitable".

Justin Stevens (centre) resigned suddenly last month. (AAP Image: Mick Tsikas)

Pressed on whether Stevens had been informed of the process, Mr Marks said the former ABC News boss was unaware the search was taking place.

ABC managing director Hugh Marks says he did not "make threats" to terminate departing news boss Justin Stevens, as senators question his sudden departure.

"Sally, I have to go about my role in the way that I see best," he said.

Asked whether he had been referring to a specific program — 7.30 turned 40 in January, multiple media outlets have noted — Mr Marks said he had "definitely" been speaking hypothetically.

"A