‘You’ve just assaulted me’: Peter Costello accused of ‘violent behaviour’ by News Corp journalist

Peter Costello, the former federal treasurer and current chairman of Nine Entertainment, has been accused of assaulting a journalist from The Australian newspaper as he refused to answer questions about the embattled media company.

But Costello has dismissed the allegations, saying “there was no assault” and that the journalist “fell over an advertising placard”.

Costello was approached at Canberra airport by The Australian reporter Liam Mendes. Mendes began asking questions about Nine’s response to allegations of sexual harassment and bullying at the company.

Mendes filmed Costello as he arrived at the airport, asking questions of him as he walked through the terminal.

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Footage published on The Australian’s website shows Costello walking towards the camera, which is moving backwards. Costello does not respond to a series of questions about Nine, its handling of recent revelations of sexual harassment and bullying in the organisation, and about Nine’s chief executive, Mike Sneesby.

In the arrivals hall, Costello moves closer towards the camera before appearing to collide with Mendes. The footage appears to show Mendes falling to the ground, although it is not clear from the video what caused Mendes, and the camera, to fall to the ground.

“You’ve just assaulted me,” Mendes says in the footage. “It’s all on camera.”

The Australian’s camera continues to follow Costello to the car park and Costello is asked questions about the incident.

“That was quite violent behaviour, Mr Costello,” Mendes says.

A Nine spokesperson denied that the chairman struck the journalist.

“After arriving at Canberra airport, the chairman [Costello] was confronted by a journalist from The Australian. In the course of filming the chairman while walking backwards, the journalist collided with an advertising placard and fell,” the spokesperson said.

“At no point did the chairman strike the journalist.”

Costello was later interviewed at the Canberra press gallery, where he was attending the opening of Nine’s new consolidated bureau. He told reporters “there was no assault – I did not lay a finger or a fist or anything else on him”.

“There was a reporter walking backwards with his phone filming,” he said.

“As I walked past him, he walked back into an advertising placard and he fell over. I did not strike him. If he’s upset about that, I’m sorry. But I did not strike him.

“I wasn’t angry. Just like you blokes here if you’re backing back, and there’s a placard behind you, you can walk into it. I’ve seen it happen a million times. I’ve seen it here at Parliament House a million times – reporters back into the bollards and fall over.”

No formal complaint of assault has been made. The Australian federal police’s ACT policing arm confirmed to the Guardian it “has not received a report relating to this matter”.

Nine has faced weeks of damaging revelations about an alleged toxic culture within its television newsroom and broader organisation.

The former news and current affairs director Darren Wick abruptly left Nine in March after 29 years with the company after complaints of sexual harassment and inappropriate behaviour. Wick has not commented publicly.

Sneesby has come under pressure about what he knew of the allegations against Wick and the terms of Wick’s departure, believed to include a payout close to $1m, most of which is entitlements.

In an email to staff, Sneesby conceded staff had been traumatised by the working environment at Nine.

“It is important we all acknowledge the trauma some of you have experienced in the past, and the distress and frustration the substance of these reports has caused,” he wrote.

“The recent reports that detail alleged serious failings of leadership in television news clearly tells me more work needs to be done to ensure we have a safe and inclusive workplace throughout Nine.”